Rank #1: Eat This, Not That: The Surprising Science of Personalized Nutrition
This episode, we’ve got the exclusive on the preliminary results of the world’s largest personalized nutrition experiment. Genetic epidemiologist Tim Spector launched the study, called PREDICT, to answer a simple but important question: do we each respond to different foods differently? And, if so, why? How much of that difference is genetic, how much is due to gut microbes, and how much is due to any one of the dozens of other factors that scientists think affect our metabolic processes? You’ve heard of personalized medicine, will there be such a thing as personalized diets? And should there be? Can teasing out the nuances of how each individual body processes different foods make us all healthier? To find out, we signed ourselves up as study participants, sticking pins in our fingers, weighing our food, and providing fecal samples, all for science—and for you, dear listeners. Listen in now as we take part in this ground-breaking study, discover our own differences, and find out the early results!
Tim Caulfield is the Canada Research Chair in Health Law and Policy at the University of Alberta. His TV show, A User’s Guide to Cheating Death, can be found on Netflix, and his most recent book is titled Is Gwyneth Paltrow Wrong About Everything? (To which we reply, pretty much!)
PREDICT and Gastropod in The New York Times
We wrote an article for The New York Times to go with this episode: check it out online here.
Find The Splendid Table online here.
The post Eat This, Not That: The Surprising Science of Personalized Nutrition appeared first on Gastropod.
Rank #2: The Bagelization of America
Today, it’s a breakfast staple, but, as recently as 1960, The New York Times had to define it for readers—as “an unsweetened doughnut with rigor mortis.” That’s right, this episode is all about the bagel, that shiny, ring-shaped, surprisingly dense bread that makes the perfect platform for cream cheese and lox. Where did it come from? Can you get a decent bagel outside New York City? And what does it have in common with the folding ping-pong table? Come get your hot, fresh bagel science and history here!
Though the bagel is most closely associated with the American Jewish community, its actual origins in Eastern Europe have become the stuff of myth. Competing tales offer explanations as to how, as early as the 1600s in Poland, Jews came to relish the bagel at childbirth, celebrations, and funerals. But, according to Maria Balinska, author of The Bagel: The Surprising History of a Modest Bread, this most Jewish of breads is likely descended from a German communion bread. The original communion bread was a large, ring-shaped bread that was baked in monasteries and shared among the congregation. “And my theory is that basically what you have is a family tree,” she told Gastropod. “One of the ancestors is the communion bread, and, from that, you have a descendant that becomes the pretzel, but you also have a descendant that becomes the bagel.”
Balinska’s theory makes even more sense when you learn that the original bagel was hard, like a pretzel. “You can’t slice it,” said Rabbi Jeff Marx, author of an essay titled “Eating Up: The Origins of Bagels and Lox,” published as a chapter in Tastes of Faith: Jewish Eating in the U.S. “All you can do is break off a piece of the bagel and dip it either in schmaltz—chicken fat—or maybe a little bit of butter.”
So how did the bagel become soft and puffy, and how did it eventually meet its soulmates, cream cheese and lox? For those stories, Balinska and Marx bring us—along with the bagel—to New York City, where the bagel helped transform America, and was itself transformed in the process. Today, bagels are found in supermarkets across the land, but many aficionados swear that a truly great bagel can never be made outside the five boroughs, due to the magical qualities of the city’s municipal water supply. To uncover the truth, we meet Francisco Migoya, head chef at Modernist Cuisine and co-author of Modernist Bread, who shipped NYC tap water to his kitchen in Seattle in order to put that belief to the scientific test. For his results, plus bagel jokes, bagel ballet, and the bagel machine that took bagels mainstream, listen in now!
Maria Balinska and The Bagel
Maria Balinska is the author of The Bagel: The Surprising History of a Modest Bread,
Rabbi Jeff Marx and “Eating Up”
Rabbi Jeff Marx is the author of an essay titled “Eating Up: The Origins of Bagels and Lox,” published as a chapter in Tastes of Faith: Jewish Eating in the U.S.
Francisco Migoya and Modernist Bread
Mary Ting Hyatt and Bagelsaurus
Mary Ting Hyatt opened Bagelsaurus in Cambridge, Massachusetts, in 2014, after operating a successful pop-in in nearby Brookline—and the lines have wrapped around the block ever since. Insider tip: On the weekends, you can skip the line and walk up to the front to buy a grab-bag dozen bagels, hot from the oven, with any type of packaged cream cheese. Or did you happen to come when the line’s not too long and you can order a sandwich? The Classic Jumbo is Cynthia’s go-to, and she loves it on an olive bagel, particularly with a roasted tomato (as per Nicky’s suggestion when she visited!).
Rank #3: Caffeine: The World’s Most Popular Drug
A tablespoon of it will kill you, but most of us feel like death without it: we’re talking about caffeine this episode. Inspired by a listener question — does green tea have more or less caffeine than black? and what about yerba mate? — Cynthia and Nicky explore the history and science of the world’s most popular drug. Listen in as we discover the curious effect of birth control pills on how our bodies process it, calculate how much of an edge it gives athletes, and learn what dolphin dissection and the American Constitution have to do with each other, and with caffeine.
Caffeine is a miracle of plant chemistry—one that evolved on four separate continents, thought experts are not entirely sure why. The prevailing hypothesis has been that caffeine functions as a pesticide, but, on this episode, food science guru Harold McGee shares more recent science that seems to contradict that. In any case, humans quickly figured out that caffeine-rich plant products—cacao beans, coffee berries, tea leaves, kola nuts, and more—made them feel great: sharper, less tired, and even a little stronger. Murray Carpenter, author of Caffeinated: How Our Daily Habit Helps, Hurts, and Hooks Us, gives us the scoop on the science behind how caffeine affects our brains and bodies, while author Bennett Alan Weinberg demonstrates caffeine’s impact by telling us the fascinating story of what happened when the stimulant finally arrived in Europe, a continent without a native source of its own.
And, finally, we answer our listener Erik’s question, and not just by saying, “It’s complicated”—although, of course, it is. All sorts of variables, from particle size to roast darkness to steeping time, affect how much caffeine is in your afternoon pick-me-up. And that’s before we even get to variations in how different people metabolize caffeine—and how other drugs and foods can speed that process up or slow it down. Could that variation help explain the current “bulletproof coffee” craze, or is it all just the placebo effect? We talk to The New York Times Magazine‘s Jenna Wortham to find out what putting butter in your coffee does to your buzz. Listen in now—you’ll never look at your espresso, English Breakfast, or energy drink the same way again.
Murray Carpenter’s Caffeinated
Journalist and caffeine fiend Murray Carpenter’s book, Caffeinated: How Our Daily Habit Helps, Hurts, and Hooks Us, includes all sorts of fascinating snippets about the drug. For example, did you know that one of Monsanto’s first products was caffeine? Or that synthetic caffeine and its natural counterpart are chemically identical, but can be differentiated using radiocarbon dating? (The carbon in synthetic caffeine comes from fossil fuels, so it’s much older than the carbon in plants.) Check out Murray’s book for all that and much more!
In her article, “You, Only Better,” Jenna Wortham meets the entrepreneur behind bulletproof coffee, Dave Asprey, as well as lots of other biohacking and self-optimization enthusiasts: read her story here, and follow Jenna on Twitter here.
The World of Caffeine
Bennett Alan Weinberg and Bonnie K. Bealer co-authored The World of Caffeine: The Science and Culture of the World’s Most Popular Drug and maintain the World of Caffeine website.
Rank #4: Breakfast of Champions
Breakfast: the most important meal of the day. Or is it? In this episode of Gastropod, we explore the science and history behind the most intentionally designed, the most industrialized, and the most argued about meal of all.
Armed with a healthy dose of caffeine chronopharmacology, we embark on a global breakfast tour that exposes the worldwide dominance of Nutella, as well as the toddler kimchi acclimatization process. Meanwhile, back in the U.S., we trace the American breakfast’s evolution from a humble mash-up of leftover dinner foods to its eighteenth-century explosion into a feast of meats, griddle cakes, eel, and pie—followed swiftly by a national case of indigestion and a granola-fueled backlash. Breakfast has been a battleground ever since: in this episode, we not only explain why, but also serve up the best breakfast contemporary science can provide.
To skip or not to skip
Much has been made about the importance of a good breakfast to a healthy lifestyle. It gives you energy to start your day, according to conventional wisdom, and scientific studies conducted a decade ago had proclaimed that eating breakfast was the key to maintaining a healthy weight.
Breakfast skippers are plagued with well-meaning spouses, partners, family members, and friends, all insisting that they should eat something in the morning. But, according to nutrition scientist P. K. Newby, that advice was based on what’s known as observational studies, in which scientists follow groups of people and observe the outcomes. The result had seemed to indicate that people who lost weight or maintained a healthy weight ate breakfast. The problem, Newby told us, is that those studies didn’t isolate breakfast as the important factor. It could be, she says, that those who lost weight also exercised more, or one of dozens of other variables.
Then, last year, a group of researchers at the University of Alabama published a study that took a more rigorous look at this question. They enlisted 300 participants and randomly assigned them to eat breakfast, to skip breakfast, or to simply go about their normal routine. After 16 weeks, they found no difference in weight loss among the three groups. Meanwhile, in a similarly controlled Cornell University study, people who skipped breakfast consumed fewer calories by the end of the day. And, in a smaller study at the University of Bath, people who skipped breakfast also seem to have consumed slightly fewer calories during the day, though they then expended slightly less energy.
Based on this new research, the bottom line, Newby says, is this: if you’re not hungry in the morning, there’s no harm in skipping breakfast when it comes to weight management. “It’s the what that is more important than the when, when it comes to breakfast,” she says, which also means that grabbing a sugary muffin, doughnut, or other pastry, just to eat something in the morning, is a worse idea than eating nothing at all.
Questioning the cult of juice
It’s January, and everybody on the Internet has embarked on a juice cleanse. But you don’t have to feel guilty for sticking to solids: without the accompanying fiber in fruit, juice delivers a straight shot of sugar.
Photography by Viktor Rosenfeld, used under a Creative Commons license.
Juice, like sugary cereals, muffins, and white bread, is “quickly metabolized,” said Newby. “These foods lead to a spike in sugar and insulin, and then it dissipates. And so then, in a short period of time, you feel hungry again.” That, she continues, can lead to overeating and weight gain. And there are long-term health consequences as well: she says diets high in refined carbohydrates are a risk factor for type 2 diabetes and cardiovascular disease.
Newby says that the most important thing to understand about breakfast is that it’s simply another meal. It may seem as though we should eat only breakfast foods—cereal, juice, bagels—at breakfast time, but, as historian Abigail Carroll explains during this episode of Gastropod, that’s just a historical hangover from nineteenth-century American health reformers. And, as Newby points out, we already know what makes a healthy meal at any time of day: put vegetables at the center of the plate, accompanied by whole grains, beans, nuts, and healthy fats.
The first cup of coffee
Though Newby says that it’s what you eat that matters, not when, that may not be the case when it comes to coffee. We spoke to neuroscience PhD candidate Steven Miller, studying at the Uniformed Services University of the Health Sciences, about chronopharmacology, or the science of how brain chemistry interacts with drugs, in order to learn how timing affects the most popular stimulant in the world: caffeine.
Photograph by trophygeek, used under a Creative Commons license.
Cortisol, the stress hormone that helps us feel alert and energized, peaks at about 8 or 9am, at least for people who work a typical 9-to-5 job and sleep during the same hours each night. Most people, says Miller, don’t need caffeine to give them a boost at a time they’re already naturally alert. In addition, drinking a caffeinated beverage at a time when you’re already sharp could lead to desensitization, which, Miller explains, means that you’ll need an increasing amount of the drug—in this case caffeine—to get the same effect.
For the best morning buzz based on brain biology, Miller recommends saving your coffee fix until 9:30am, when cortisol levels are starting to drop off.
He admits, though, that his recommendation doesn’t hold true for everyone: anyone whose sleep schedule is not regular or who works evening or night shifts will have a different cortisol production rhythm. In fact, he actually doesn’t follow his own chronopharmacological advice. Miller told Gastropod that, as a neuroscience PhD student, he works long, irregular hours and gets little sleep, and he always starts off his day, at any hour, with an extra strong caffeinated beverage.
The most capitalist meal of all
Miller’s decision to design his coffee routine around his work schedule, rather than biology, isn’t surprising given the history of breakfast. As we learn from journalist Malia Wollan, while breakfast foods may be different all around the world, it’s the first meal to change in immigrant households. And, as Three Squares author Abigail Carroll explains, those classic American breakfast foods can be traced directly back to the Industrial Revolution and its transformation of labor—combined with some entrepreneurial innovations in processing, packaging, and marketing that were first pioneered in breakfast cereal but went on to transform the American diet. To learn more about the revolutionary history, global peculiarities, and surprising science of breakfast, listen to our latest episode!
Thanks to all of you who wrote or called in to share your breakfast stories—we heard tell of pumpkin kasha, rabbit and Stilton casserole, memelitas, and coleslaw, proving (as if we didn’t already know) that Gastropod listeners are a most unusual and fascinating bunch.
What Kids Around the World Eat for Breakfast
Baby’s First Kimchi
After Malia told us that YouTube is home to an entire subgenre of videos documenting Korean babies’ first taste of kimchi, we couldn’t resist watching one or two. Or three. Or four… In fact, it’s a miracle this episode ever got made!
PK Newby’s Shakshouka
Abigail Carroll’s Three Squares
As Nicky mentions during the episode, historian Abigail Carroll’s 2013 book, Three Squares: The Invention of the American Meal, tells the story behind breakfast, lunch, and dinner. It’s fascinating, fun, and highly recommended reading.
Read Steven Miller’s fascinating exploration of the chronopharmacology of caffeine here at his blog post, “The best time for your coffee.”
Vintage Breakfast Cereal Ads
You may have caught a couple of jingles during the episode: one from a 1960 cornflake ad, and another from a 1936 Rice Krispies ad. They came from the extraordinary Prelinger Archives, a collection of over 60,000 “ephemeral” (advertising, educational, industrial, and amateur) films founded by Rick Prelinger and since acquired by the Library of Congress. Browse it here, and prepare to lose the rest of your day.
Aspire Food Group
This episode was sponsored by the Aspire Food Group, an award-winning company with farming projects in the US, Ghana, and Mexico, whose goal is to feed the world, sustainably, through insects and insect-derived foods. As part of the sponsorship, we cooked with their finely milled cricket flour. Nicky made Hoppin’ Good Banana Oat Cricket muffins, which were a huge hit with her neighbors (though she personally felt the recipe was a little too healthy), and Cynthia and her partner Tim added some cricket flour to their blueberry pancakes. If you’d like to try them yourself, here’s the recipe, and Gastropod listeners get a 10 percent discount on both flour and whole cricket using the code “Gastropodcast” on their online store (enter it on the final page before confirming your purchase).
Buttermilk Blueberry Cricket Pancakes
Mix together these dry ingredients: one cup of white flour, 1/4 cup of cricket powder (substituting for 1/4 cup of flour), 2 tablespoons of sugar, 1 teaspoon of baking powder, and 1/2 teaspoon baking soda. In a separate bowl, mix 1 beaten egg, 1 1/3 cup of buttermilk, 1 tablespoon of oil. Mix the wet ingredients together with the dry. Tim found the batter a little thick, and so he added a splash more buttermilk. Then he poured a small amount of batter onto a hot, lightly oiled griddle, and pressed frozen blueberries into each as they cooked, then flipped them over. Enjoy!
Austin-based Hopper Foods also sent us some of their prototype Berry & Vanilla Cricket Granola (so, so good!), and a couple of their tasty Hopper Energy Bars. The granola is coming soon, but listeners can get 10 percent off the energy bars with the code “Gastropodcast.”
Rank #5: Say Cheese!
Cheese is the chameleon of the food world, as well as one of its greatest delights. Fresh and light or funky and earthy, creamy and melty or crystalline and crumbly—no other food offers such a variety of flavors and textures.
But cheese is not just a treat for the palate: its discovery changed the course of Western civilization, and, today, cheese rinds are helping scientists conduct cutting-edge research into microbial ecology. In this episode of Gastropod, we investigate cheese in all stinking glory, from ancient Mesopotamia to medieval France, from the origins of cheese factories and Velveeta to the growing artisanal cheese movement in the U.S. Along the way, we search for the answer to a surprisingly complex question: what is cheese? Join us as we bust cheese myths, solve cheese mysteries, and put together the ultimate cheese plate.
The Secret History of Cheese, or, Why the Cheese Origin Story is a Myth
This is the story you’ll often hear about how humans discovered cheese: one hot day nine thousand years ago, a nomad was on his travels, and brought along some milk in an animal stomach—a sort of proto-thermos—to have something to drink at the end of the day. But when he arrived, he discovered that the rennet in the stomach lining had curdled the milk, creating the first cheese. But there’s a major problem with that story, as University of Vermont cheese scientist and historian Paul Kindstedt told Gastropod: the nomads living in the Fertile Crescent of the Middle East in 7000 B.C. would have been lactose-intolerant. A nomad on the road wouldn’t have wanted to drink milk; it would have left him in severe gastro-intestinal distress.
Kindstedt, author of the book Cheese and Culture, explained that about a thousand years before traces of cheese-making show up in the archaeological record, humans began growing crops. Those early fields of wheat and other grains attracted local wild sheep and goats, which provide milk for their young. Human babies are also perfectly adapted for milk. Early humans quickly made the connection and began dairying—but for the first thousand years, toddlers and babies were the only ones consuming the milk. Human adults were uniformly lactose-intolerant, says Kindstedt. What’s more, he told us that “we know from some exciting archaeo-genetic and genomic modeling that the capacity to tolerate lactose into adulthood didn’t develop until about 5500 BC”—which is at least a thousand years after the development of cheese.
The real dawn of cheese came about 8,500 years ago, with two simultaneous developments in human history. First, by then, over-intensive agricultural practices had depleted the soil, leading to the first human-created environmental disaster. As a result, Neolithic humans began herding goats and sheep more intensely, as those animals could survive on marginal lands unfit for crops. And secondly, humans invented pottery: the original practical milk-collection containers.
In the warm environment of the Fertile Crescent region, Kinstedt explained, any milk not used immediately and instead left to stand in those newly invented containers “would have very quickly, in a matter of hours, coagulated [due to the heat and the natural lactic acid bacteria in the milk]. And at some point, probably some adventurous adult tried some of the solid material and found that they could tolerate it a lot more of it than they could milk.” That’s because about 80 percent of the lactose drains off with the whey, leaving a digestible and, likely, rather delicious fresh cheese.
Cheese Changed the Course of Western Civilization
With the discovery of cheese, suddenly those early humans could add dairy to their diets. Cheese made an entirely new source of nutrients and calories available for adults, and, as a result, dairying took off in a major way. What this meant, says Kindstedt, is that “children and newborns would be exposed to milk frequently, which ultimately through random mutations selected for children who could tolerate lactose later into adulthood.”
In a very short time, at least in terms of human evolution—perhaps only a few thousand years—that mutation spread throughout the population of the Fertile Crescent. As those herders migrated to Europe and beyond, they carried this genetic mutation with them. According to Kindstedt, “It’s an absolutely stunning example of a genetic selection occurring in an unbelievably short period of time in human development. It’s really a wonder of the world, and it changed Western civilization forever.”
Tasting the First Cheeses Today
In lieu of an actual time machine, Gastropod has another trick for listeners who want to know what cheese tasted like 9,000 years ago: head to the local grocery store and pick up some ricotta or goat’s milk chevre. These cheeses are coagulated using heat and acid, rather than rennet, in much the same way as the very first cheeses. Based on the archaeological evidence of Neolithic pottery containers found in the Fertile Crescent, those early cheeses would have been made from goat’s or sheep’s milk, meaning that they likely would have been somewhat funkier than cow’s milk ricotta, and perhaps of a looser, wetter consistency, more like cottage cheese.
“It would have had a tart, clean flavor,” says Kindstedt, “and it would have been even softer than the cheese you buy at the cheese shop. It would have been a tart, clean, acidic, very moist cheese.”
So, the next time you’re eating a ricotta lasagne or cheesecake, just think: you’re tasting something very similar to the cheese that gave ancient humans a dietary edge, nearly 9,000 years ago.
Camembert Used to be Green
Those early cheese-making peoples spread to Europe, but it wasn’t until the Middle Ages that the wild diversity of cheeses we see today started to emerge. In the episode, we trace the emergence of Swiss cheese and French bloomy rind cheeses, like Brie. But here’s a curious fact that didn’t make it into the show: when Gastropod visited Tufts microbiologist Benjamin Wolfe in his cheese lab, he showed us a petri dish in which he was culturing the microbe used to make Camembert, Penicillium camemberti. And it was a gorgeous blue-green color.
Wolfe explained that according to Camembert: A National Myth, a history of the iconic French cheese written by Pierre Boisard, the original Camembert cheeses in Normandy would have been that same color, their rinds entirely colonized by Wolfe’s “green, minty, crazy” microbe. Indeed, in nineteenth-century newspapers, letters, and advertisements, Camembert cheeses are routinely described as green, green-blue, or greenish-grey. The pure white Camembert we know and love today did not become the norm until the 1920s and 30s. What happened, according to Wolfe, is that if you grow the wild microbe “in a very lush environment, like cheese is, it eventually starts to mutate. And along the way, these white mutants that look like the thing we think of as Camembert popped up.”
In his book, Boisard attributes the rapid rise of the white mutant to human selection, arguing that Louis Pasteur’s discoveries in germ theory at the start of the twentieth-century led to a prejudice against the original “moldy”-looking green Camembert rinds, and a preference for the more hygienic-seeming pure white ones. Camembert’s green origins have since been almost entirely forgotten, even by the most traditional cheese-makers.
Listen to this week’s episode of Gastropod for much more on the secret history and science of cheese, including how early cheese bureaucracy led to the development of writing, what studying microbes in cheese rinds can tell us about microbial ecology in our guts, and why in the world American cheese is dyed orange. (Hint: the color was originally seen as a sign of high quality.) Plus, Gastropod will help you put together the world’s most interesting cheese plate to wow guests at your next dinner party. Listen here for more!
Microbes Make the Cheese
In the episode, Heather Paxson describes the struggles she and her colleagues went through as part of a committee responsible for writing this American Academy of Microbiology FAQ on microbes and cheese, “Microbes Make the Cheese,” published in February 2015 and available as a free PDF here.
Paul Kindstedt is a professor in the Department of Nutrition and Food Sciences at the University of Vermont, where he studies the chemistry, biochemistry, structure, and function of cheese. His book, Cheese and Culture: A History of Cheese and its Place in Western Civilization, came out in 2012.
At his lab at Tufts University, microbiologist Benjamin Wolfe studies how microbes from food (mostly cheese!) interact, in order to tease out the ecological and evolutionary forces that shape microbial diversity. He is co-founder of MicrobialFoods.org, an online publication exploring the science of fermented foods.
Cheese Rind Communities Provide Tractable Systems for In Situ and In Vitro Studies of Microbial Diversity
This paper, published in the journal Cell in July 2014, was co-authored by Benjamin Wolfe, Julie E. Button, Marcela Santarelli, and Rachel J. Dutton. The team surveyed 137 European and North American cheeses to assess microbial diversity, with some fascinating results. At the time, Wolfe was working in Rachel Dutton’s lab at Harvard’s FAS Center for Systems Biology. A Gastropod listener and current post-doc in Dutton’s lab, Kevin Bonham, recently wrote a three-part essay at Scientific American that goes into detail about the process for DNA-sequencing a cheese rind, and how to turn that data into useful information.
To eat the rind or not?
You may have noticed that some eaters scorn the rinds of cheeses, from the soft fuzzy white carpet that envelops brie to the tougher edge of an aged cheddar, while others tuck right into them. Which approach is correct? The answer depends on what kind of rind it is—as well as your own comfort level with microbes.
Some rinds today are covered with wax, and others, such as England’s Montgomery Cheddar, are surrounded by cloth, neither of which are edible. But for all the rest, the rind is what microbiologists such as Ben Wolfe call a “biofilm”—an entire ecosystem of microbes that colonize the cheese surface, gluing themselves together. Historically, the rind creates a method of preservation, a surface “to keep [the cheese] from being damaged and make it easy to transport. So people just let these rinds develop.” These microbial rinds are perfectly safe for consumption, though they have a different, sometimes stronger, taste than the cheese itself. So: Eat the rind or not? Heather Paxson, who unhesitatingly ate the rind on a St. Nectaire during an afternoon of cheese-tasting with Gastropod, says “It’s purely a matter of taste.”
As we explain in the episode, Ben Wolfe has become something of a “cheese doctor,” with cheese-makers sending him their “Frankencheeses” in the mail, in order to figure out what went wrong. Meanwhile, listener “Moldy in Avignon” sent us an email with the subject “Gross Cheese Mystery,” and a photograph of really, really old cheeses for sale in the Avignon market. We consulted with Ben, who shared his own photos of brown, nasty-looking French cheeses for sale at the Slow Food Festival in Bra, Italy. Apparently, these kinds of super-aged cheeses are meant for eating, though the cheese seller in this short video explains they are hard to find these days and much less popular than they used to be.
The brown dust is actually microscopic cheese mites: Wolfe calls them the “gophers” of the cheese world, as they eat into the rind, aerating it as well as increasing the surface area available for microbial colonization (and thus flavor development). They’re common in cheese aging, although in the U.S. they’re usually regarded as a pest, and cheeses are carefully brushed to remove them. Here’s footage of a cheese mite munching on microbial hyphae, filmed at the Dutton lab.
Very old cheeses (aged for up to five years) covered in craggly molds and a fine dust of cheese mites. (Left) Photographed by Ben Wolfe for sale at the Slow Food Festival in Bra, Italy. (Right) As photographed by listener “Moldy in Avignon.”
Cheese stories, cheese ads, and Wallace & Gromit
This episode wouldn’t have been nearly as much fun without all your cheese stories: thanks to all of you who wrote or called in, and particularly to Elana Lubin, Roz Cummins, Emily Lo Gibson, Mike Simonovich, Jenny Morber, Etta Devine, Tasha from the Boston area, and Doug from Perth. We sampled audio from Alex Crowley’s Wallace & Gromit “The Cheesesnatcher” claymation, as well as a 1986 Velveeta ad, a 1958 Kraft ad, and a “Time for Timer” Saturday morning cartoon PSA from the 1970s.
Rank #6: We’ve Lost It: The Diet Episode
Diet dreams are splashed across magazine covers and blare from the T.V., offering tips and tricks, that will, readers and viewers are promised, make weight loss easy and fast. Diet books making similar claims can be found at the top of the best-seller list without fail, every January. But where does this obsession with losing weight to reach some kind of idealized body type come from? How long have gurus and doctors alike made millions from the West’s preoccupation with the “d” word, and why do strange fads such as chewing each bite hundreds of times stick around for centuries? This episode, we explore the history of diets, before asking a scientist: Does anything actually work?
Nobody knows exactly how long humans have elevated a particular physical ideal as the standard, with anyone who who weighs more considered “over.” But we do know where and when the word “diet” was invented: ancient Greece. In is original context, “diaita” wasn’t solely focused on eating certain foods to achieve weight loss—it was meant to represent an entire way of life, encompassing food, drink, lifestyle, and exercise. With the exception of running naked and regular vomiting, ancient Greek diet recommendations still sound like pretty sensible advice. “They didn’t get everything right,” Louise Foxcroft, author of Calories and Corsets: A History of Dieting Over 2,000 Years, told Gastropod, “but they did know that a healthy mind and a healthy body made for a healthy society”—for individuals and for society.
But the ancient Greek influence on diet culture had some built in biases that still resonate today. According to Foxcroft, the ideal body was male. “The male is quite slim, he’s quite muscled, and he’s very beautiful,” she told us. “Women can’t live up to that—or weren’t thought to be able to live up to that. So the onus on diet and on having an ideal body—it’s always been a much more difficult concept for women, and that’s reflected in our modern diet culture as well.” At the same time, early Christian concepts of gluttony, temptation, and morality condemned fat as sin written on the body—another idea that has shaped Western thought on food and weight for millennia.
It took another few hundred years for the idea of the diet guru to become an entrenched figure in the West. This episode, we unearth such gems as the first diet bestseller, meet the proto-Atkins, and discover that today’s celebrity dieters, from Oprah to the Kardashians, are really only following in the footsteps of Lord Byron. Finally, we talk with Susan Roberts, nutritionist at Tufts University and one of the experts on a panel that recently ranked forty well-known diets in order of effectiveness for U.S. News & World Report. Is there any science behind the low-carb craze? What does the Mediterranean Diet actually mean? And does any diet actually deliver the long-term weight loss they all promise? Listen in!
- An earlier version of this episode incorrectly stated that protein is broken down to make ketones; in fact, fat is broken down to make ketones. We apologize for the mistake.
Louise Foxcroft is a writer, historian, and broadcaster. In addition to Calories and Corsets: A history of dieting over 2,000 years, she’s written on the topics as diverse as the history of the menopause and London’s Serpentine lake.
Susan Roberts and the iDiet
Susan Roberts is senior scientist and director of the Energy Metabolism Laboratory at Tufts University, where she holds a dual appointment in nutrition and psychiatry. She served on the panel of experts that recently reviewed and ranked diets in order of effectiveness for U.S. News and World Report. And she has developed her own diet, the iDiet, which she notes is the only diet program ever clinically shown to reduce hunger during weight loss.
Lindy West, Susie Orbach, and Other Awesome Ladies
This episode, we featured clips of writer, comedian, and activist Lindy West talking to the Food Psych podcast about Weight Watchers and in conversation with Anne Summers at Melbourne’s Wheeler Centre, discussing the moral judgement attached to fat. We also included a clip of Susie Orbach, author of Fat is a Feminist Issue, talking to The Guardian. And we recommend enjoying Margaret Cho’s “Persimmon Diet” routine in full, as well as Amy Schumer’s nutritionist sketch. Huge thanks to our amazing volunteer Ari Lebowitz for finding these clips!
For a transcript of the show, please click here. Please note that the transcript is provided as a courtesy and may contain errors.
Rank #7: To Eat or Not to Eat Meat
With flexitarianism on the rise throughout the developed world, and everyone from Bill Clinton to Beyoncé endorsing the benefits of a vegetarian or vegan diet, it can sometimes seem as though meat is just a bad habit that the majority of us are too weak-willed to kick. But is giving up meat morally superior, healthier, and better for the planet, as its advocates insist? This episode, we fearlessly dive into the long, tangled history and surprisingly nuanced science behind those claims. Listen in now for the truth on Pythagoras, cow farts, and more.
The ideal of a non-violent diet goes back to the origins of most world religions. Adam and Eve’s pre-lapsarian diet was plant-based, while in the East, Hinduism, Buddhism, and Jainism all embraced the concept of ahimsa, or non-violence toward living things—even if many Hindus and Buddhists aren’t necessarily vegetarian themselves. We speak with author Colin Spencer, Gastropod listener and Jain Purvi Shah, and theologian Jo Ann Davidson to understand the genesis of these beliefs and their evolution throughout human history.
In the 16- and 1700s, new scientific discoveries were employed to adjudicate the question of whether eating meat was morally wrong: author and activist Tristram Stuart explains that, while vegetarian advocates held up the similarity of human and animal nervous systems to condemn the suffering inflicted by meat-eating, their opponents used the newly invented microscope to demonstrate that even the most rigorous Jain is still killing untold quantities of microbial and insect life every time they sit down to dinner. Today, the debate over animal rights and an animal’s role as a potential source of food still rages.
But the claims that giving up meat will reduce heart attacks and save the planet—they must be much easier to prove, right? Not so fast: we speak to nutritionist Frankie Phillips, epidemiologist Corinna Koebnick, rancher Nicolette Hahn Niman, and researchers Gidon Eshel and Marco Springmann to understand the science behind a meat-free diet’s reported health and environmental benefits—and figure out its flaws. As we discover this episode, nothing about eating meat or not eating meat is as clear cut as it seems.
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Jo Ann Davidson
Colin Spencer and The Heretic’s Feast
Tristram Stuart and The Bloodless Revolution
Tristram Stuart is author of The Bloodless Revolution: A Cultural History of Vegetarianism from 1600 to Modern Times, as well as a food waste activist. You can watch his TED talk on the subject here, and then learn more about the campaigning organization he founded, Feedback.
Corinna Koebnick is an epidemiologist with Kaiser Permanente of Southern California. For this episode, we discussed her research paper on the implications of a long-term vegetarian diet for a healthy pregnancy.
Marco Springmann is a researcher at the Oxford Martin Programme on the Future of Food, based at Oxford University. His paper, “Analysis and valuation of the health and climate change co-benefits of dietary change,” was published in the Proceedings of the National Academy of Sciences last year.
Nicolette Hahn Niman and Defending Beef
Nicolette Hahn Niman is an environmental lawyer, rancher, and author of Defending Beef: The Case for Sustainable Meat Production, as well as Righteous Porkchop: Finding a Life and Good Food Beyond Factory Farms.
Gidon Eshel is a professor of environmental science and physics at Bard College. Our discussion was focused on his 2014 paper, “Land, irrigation water, greenhouse gas, and reactive nitrogen burdens of meat, eggs, and dairy production in the United States.”
For a transcript of the show, please click here. Please note that the transcript is provided as a courtesy and may contain errors.
Rank #8: Ripe for Global Domination: The Story of the Avocado
Avocados are on a roll. More precisely, they’re on toast—a lot of toast. Last summer, British Vogue reported that more than three million new photos of avocado toast are uploaded to Instagram every day. But how did this humble fruit, originally named after testicles, get from its Mexican forest home to a tattoo on Miley Cyrus’s upper arm? This episode, we unravel the avocado’s amazing journey, a story that involves not only conquistadors and cartel violence, but also a Southern California postman and actress Angie Dickinson lounging in a white leotard. And we discover where the avocado is headed next—a place where it’s known as the butter fruit, and often consumed in shake form. Listen in now for all this creamy green goodness and more.
Nobody is sure exactly where the avocado first came from, but the earliest evidence for its consumption dates back 10,000 years, from the remains of settlements in central Mexico. The avocado tree itself is, of course, much more ancient, so ancient that it had already been a so-called “evolutionary ghost” for three thousand years by that point. Its partners in evolution—the giant, elephant-like gomphotheres and three-ton ground sloths that dined on its fruit in return for transporting and then pooping out its giant seed—went extinct soon after the first bipedal apes arrived in the region. Rodents, jaguars, and eventually humans stepped in as dispersal mechanisms, albeit significantly less effective ones. The flourishing avocado forests that carpeted much of Mesoamerica during the Cenozoic era dwindled and died out. And, as Mary Lu Arpaia, who runs the avocado breeding program at the University of California, Riverside, explained, the avocado became a backyard fruit, enjoyed by first the indigenous peoples and later the conquistadors, but rarely cultivated intensively—until recent decades.
The story of this anachronistic fruit’s astonishing resurgence hinges on a trade agreement. With the help of financial columnist Brook Larmer, we explore the machinations that turned the avocado into green gold. But the avocado’s rise is more than just a business story: smashed up on a piece of toasted bread, avocado has become a signifier of a certain lifestyle, popularized by none other than Gwyneth Paltrow. Although journalist Lauren Oyler warned us that trying to pinpoint the dish’s origins is “a fool’s errand,” she nonetheless guides us through the celebrity-strewn story, dissecting avocado toast’s allure—and expense. Today, avocado is everywhere: it’s worshipped for its heart-healthy fats, and blamed for bankrupting a generation. But, according to Larmer, we’re nowhere near peak avocado yet. Listen in now for the next chapter in the avocado’s astonishing history.
As promised, Angie Dickinson in a white leotard, advertising California avocados in the 1980s.
Mary Lu Arpaia
Mary Lu Arpaia leads the avocado breeding program at the University of California, Riverside. Cynthia visited her and her colleague Erich Focht to learn more about the avocado and their work—and to taste the avocado varieties of the future. We’ll have much more on that—including a new variety that is reportedly better than the Hass—in our special Gastropod Super-Fan newsletter, which goes out to supporters every two weeks. Find out how you can get in on that here.
Luis Mario Tapio Vargas
Luis Mario Tapio Vargas leads the water and soil management research program at Mexico’s National Research Institute for Forests and Agriculture (INIFAP).
The Food Explorer: The Adventures of the Globe-Trotting Botanist Who Transformed What America Eats, by Daniel Stone
We spent our last episode telling this story, but we brought Daniel Stone back this week to tell us about Fairchild’s role in the origin of the world’s most popular avocado variety, the Hass. If you haven’t already, check out Stone’s new book, for more Fairchild fun!
Note on language
Please note that this episode contains two swear words.
For a transcript of the show, please click here. Please note that the transcript is provided as a courtesy and may contain errors
The post Ripe for Global Domination: The Story of the Avocado appeared first on Gastropod.
Rank #9: Can Diet Stop Alzheimer’s?
Every three seconds, someone in the world develops Alzheimer’s disease. It’s a devastating disease: millions of people, as well as their caretakers, spend years dealing with disabling disorientation and memory loss. Today, it’s the sixth leading cause of death in the U.S. By 2050, an estimated 15 million people in America will have Alzheimer’s—the combined populations of New York, Chicago, and Los Angeles. But, after years of failed drug trials, scientists are now realizing that the disease begins with structural changes in the brain decades before sufferers show any symptoms. And some researchers now believe that diet may be the most important factor in determining whether or not those brain changes take place. Listen in now to find out: Can changing what you eat prevent Alzheimer’s?
In 1906, German psychiatrist Alois Alzheimer dissected and stained the brain of a deceased patient. Auguste Deter had died in her fifties, after suffering from memory loss and delusions. In his postmortem examination, Alzheimer noticed Deter’s brain was clogged with gunk: agglomerations of proteins had formed pathological structures that are now called amyloid plaques and tau tangles. Though dementia has been recognized for millennia—the ancient Greek physician Galen called dementia “morosis”—Dr. Alzheimer was the first to see the physical effects of the disease’s most common cause on the brain.
Today, more than a century later, and despite hundreds of millions of dollars spent studying it, there is no cure for Alzheimer’s disease, and not much in the way of treatment, either. There are a few medications that help manage symptoms, but as Lisa Mosconi, a specialist in neuroscience and nuclear medicine and associate director of the Weill Cornell Alzheimer’s Prevention Clinic, told Gastropod, “They work for a few years, for some people they work longer, for some people they don’t work at all. But they can’t stop Alzheimer’s, so they’re not a long-term solution.” In part, this seems to be because drugs designed to cure Alzheimer’s have focused on ridding the brain of amyloid plaques. Some of them even managed to remove the plaques, Mosconi told us. “But cognition did not improve,” she said. “There were an enormous amount of side effects, and some patients actually got worse. Some died. And that really begs the question: What are we doing wrong?”
For Mosconi and her colleague, Richard Isaacson, who founded and directs the Alzheimer’s Prevention Clinic, the first of its kind in the U.S. and still one of only a few in the world, the answer to that question has involved a shift in approach: from cure to prevention. Over the past decade, observational studies have revealed patterns that seem to link Alzheimer’s with exercise, sleep, cognitive stimulation, and, especially, diet. Based on the patterns in the data, it seems as though such so-called lifestyle factors make up to half a person’s risk of developing Alzheimer’s.
But, of course, correlation is not causation. And so Isaacson and Mosconi have set out to see whether they can prove that implementing changes in diet and lifestyle in middle age can actually prevent Alzheimer’s. Working with a cohort of healthy patients with a family history of the disease, Isaacson and Mosconi study whether a rigorous diet and exercise regime can actually prevent Alzheimer’s disease, or at least delay its onset. Meanwhile, Mosconi also puts her patients in a brain scanner to look for early signals of Alzheimer’s—and she’s seeing how what people eat is the biggest factor in changing brain structure.
These findings are brand new, but the emerging evidence for the power of lifestyle changes for Alzheimer’s prevention is now so compelling that the Alzheimer’s Association has just launched a $20 million, two-year clinical trial to study just that in 2,000 volunteers around the U.S. So, what should you eat to protect your brain? Listen in now for Gastropod’s scoop on this exciting new research.
Lisa Mosconi is a specialist in neuroscience and nuclear medicine, as well as the associate director of the Weill Cornell Alzheimer’s Prevention Clinic. You can find links to her publications here. She’s also the author of Brain Food: The Surprising Science of Eating for Cognitive Power.
Richard Isaacson is a neurologist and the founder of the Weill Cornell Alzheimer’s Prevention Clinic. His most recent paper based on his work at the clinic can be found here, and he expects to publish full results later this year.
FINGER and POINTER
If you’re looking for more information on the FINGER study, the results were published here in 2015. The POINTER study is underway now, you can find more information here. (Together, are they the Pointer Finger? Sorry, we couldn’t resist.)
Illustration by Lauren Cierzan
Sloan Foundation and Burroughs Wellcome Fund
Speaking of thanks, we’d like to thank the Alfred P. Sloan Foundation for the Public Understanding of Science, Technology, and Economics for supporting our science coverage, as well as the Burroughs Wellcome Fund for supporting our coverage of biomedical research.
Rank #10: Guts and Glory
What does it mean when your stomach rumbles? How do our bodies extract nutrients and vitamins from food? Does what you eat affect your mood? Digestion is an invisible, effortless, unconscious process—and one that, until recently, we knew almost nothing about. On this episode of Gastropod, we follow our food on its journey to becoming fuel, from the filtered blood that helps slide food into the stomach, to the velvet walls and rippling choreography of the small intestine, to the microbial magic of the colon and out the other end. And we do it by visiting the world’s most sophisticated artificial gut at dinner time—a plumbing marvel named TIM that chews, swallows, squeezes, farts, and poops just like the real thing.
Before the invention of refrigeration, cadavers that early scientists dissected to learn about human physiology usually had their guts removed, to help reduce the stink. As a result, the digestive system largely remained a black box—food went in, the processed remains came out—until a window opened that black box in 1822, in the form of a bullet hole in the stomach of Alexis St. Martin. An impoverished French Canadian trapper, he worked for the American Fur Company until he was accidentally shot. As Mary Roach, author of Gulp: Adventures on the Alimentary Canal, told Gastropod, a surgeon named William Beaumont discovered that the bullet hole offered a literal opening into the mysterious workings of the stomach, because St. Martin’s “breakfast kind of spilled out.” Roach says it’s unclear whether Beaumont did his best to heal St. Martin: “He says that he did. But, I’m just guessing, maybe he kind of saw an opportunity here.”
For more than a decade, the two enjoyed a strange relationship, each dependent on the other. St. Martin lived at Beaumont’s house, and Beaumont took advantage of the unhealed stomach opening to dangle food in on a string, to learn that stomach acid can digest food even without the stomach’s vise-like squeeze. Today, Beaumont is recognized as one of the fathers of modern physiology.
TIM 1, with stomach and small intestine (left); TIM’s inputs are stored on shelves at the side of the cabinet (right, top); TIM’s chewing machine (right, bottom). Photos by Nicola Twilley.
Though scientists have long moved past the food-on-a-string method of research, the current techniques for investigating how we process our food, as digestion is occurring in our bodies, remain invasive and expensive. And so researchers also rely on sophisticated models of the gut that attempt to mimic every critical stop along the thirty-odd feet our of digestive systems. To learn what these models can teach us, we traveled to the Netherlands to visit TIM, the world’s most sophisticated model gut, at the Dutch public-private research organization TNO. TIM’s entire system fills two huge beige cabinets of silicone tubes and metal valves, from its mouth input funnel to the fart tube that removes the smelly gas produced at the other end.
TIM’s system is larger than life—but biologist Don Ingber and his colleaugues at the Wyss Institute for Biologically Inspired Engineering at Harvard University have shrunk the large and small intestines down to two small, flexible squares of clear rubber. On each “organ-on-a-chip,” nearly invisible tubes are lined with cells from our intestinal walls—cells whose function mimics the activity in our own real intestinal walls.
To compare these models to the real thing, we spoke with Giulia Enders, doctor and author of Gut, The Inside Story of our Bodies’ Most Underrated Organ, and perhaps the biggest gut fan of all. Enders explains how the gut acts as a second brain in the body, with its own form of consciousness. By the time we’re through, you’ll have a new appreciation for the gut as a thing of beauty—and you may never be embarrassed by a rumbling stomach again. Listen in now!
Giulia Enders is a medical doctor and author currently studying for her Ph.D. in gastroenterology at the Institute for Microbiology and Hospital Hygiene in Frankfurt. She’s the author of Gut: The Inside Story of Our Body’s Most Underrated Organ.
Susann Bellman, Mans Minekus, and TIM, TNO
TIM 2, the large intestine. Photo by Nicola Twilley.
Don Ingber is the founding director of the Wyss Institute for Biologically Inspired Engineering at Harvard and lead inventor of the organs-on-a-chip.
Rank #11: Out of the Fire, Into the Frying Pan
From rainbow-hued enameled stew pots to lightweight nonstick frying pans, the metal and ceramic vessels we use to heat our food are such an everyday aspect of the kitchen that they’re easy to take for granted. But make no mistake: the invention of the pot was, after fire, one of the most important innovations in cooking. You’ll want to hug your favorite skillet after coming along with us on this journey, which ranges from some of the earliest clay pots ever found in what’s now the Sahara Desert, to the British round-bellied cast-iron number that kickstarted the Industrial Revolution, to a legal challenge in Ohio that raised the question of Teflon’s health and environmental impact. Plus, can science help us find the perfect pot or pan? Listen in to find out.
In our last episode, we covered one of the most important innovations in human history: cooking food over fire. But, although cooking may have made us human, it is the invention of pots that made us into cooks. As Bee Wilson, author of Consider the Fork and frequent Gastropod guest, explained: “Pots led to cuisine itself. To me, it’s the great beginning of cookery.” Tens of thousands of years ago, the invention of pots brought with it life-changing benefits: prolonged cooking could slowly break down plants like yams and cassava that would have otherwise been inedible; the process releases more starches from foods and therefore more calories; long boiling kills harmful microbes and thus makes food safer; softened food like grains could be fed to babies, allowing children to be weaned earlier and leading to yet more children and early population growth; and finally, the ability to create dishes that were cooked slowly and indirectly, mingling many different ingredients, made the business of eating a lot more delicious.
But how did we get from those earliest examples of clay cooking containers to the incredible variety of shapes, sizes, and materials found in kitchen cabinets around the world today—and what stories can those pots and pans tell over the years? In this episode, Gastropod visits Blu Skillet in Seattle, Wash., to watch a carbon steel pan being forged and smithed by hand. Julie Dunne, a.k.a. @thepotlady, a biomolecular archaeologist at the University of Bristol, describes her discovery of the earliest known pots used to cook vegetables. Metallurgist Richard Williams introduces us to Abraham Darby, whose breakthrough in cast iron pot-making technology funded the R&D that led to the Industrial Revolution. Brown University epidemiologist David Savitz joins us to discuss the question of whether or not the chemicals involved in Teflon pans cause health issues. Finally, food science guru Harold McGee, author of On Food and Cooking, helps us answer a seemingly impossible question: What makes the perfect pan? Listen in now!
Finished Blu Skillet pans. Photo by Cynthia Graber.
Thanks to Patrick Maher and Caryn Badgett, who welcomed Cynthia into Blu Skillet‘s studio in Seattle’s Ballard neighborhood to watch a pan being made. For locals, Blu Skillet hosts studio sales twice a year; otherwise, if you’re in the market for one of their hand-made pans, you’ll have to try your luck in their monthly lottery. They’ve been selling out regularly ever since this piece in Cook’s Illustrated on carbon steel that featured their work.
Bee Wilson’s Consider the Fork
Bee Wilson is a food writer and author of Consider the Fork: A History of How we Cook and Eat, among other books. She’s a Gastropod regular, having starred in our very first episode, “The Golden Spoon,” as well as “First Foods: Learning to Eat.” You can find engineer Chuck Lemme’s reflections on the ideal pot in the 1988 Proceedings of the Oxford Symposium on Food & Cookery.
Julie Dunne is a biomolecular archaeologist at the University of Bristol. Her study on the potsherds found in Libya can be found here, and she’s current working on a multi-year project called Peopling the Green Sahara, which explores the ecological and demographic history of the region.
When metallurgist Richard Williams was asked to examine a cast-iron pot in the collection of the collection of the Ironbridge Gorge Museum Trust, he uncovered a story that led from kitchen wares to the Industrial Revolution.
Brown University epidemiologist David Savitz was asked to look into the health impacts of a chemical used in making Teflon called PFOA, as part of the settlement in a class action lawsuit filed by people in Ohio and West Virginia who lived near a DuPont manufacturing factory. The C8 panel he was part of published research on the likely links between PFOA in drinking water and a number of health outcomes. For more detail, here’s a long Mother Jones article on the lawsuit. Dupont and the chemical industry as a whole have since phased out PFOA, though there’s a debate about whether the replacement chemicals are significantly safer.
Harold McGee writes about the chemistry of food and cooking, most famously in his book On Food and Cooking. He’s starred on Gastropod before, trying to help Cynthia overcome her dislike of cilantro, as well as explaining the mysteries of caffeine.
For a transcript of the show, please click here. Please note that the transcript is provided as a courtesy and may contain errors
Rank #12: Secrets of Sourdough
Today, you can find a huge variety of breads on supermarket shelves, only a few of which are called “sourdough.” For most of human history, though, any bread that wasn’t flat was sourdough—that is, it was leavened with a wild community of microbes. And yet we know surprisingly little about the microbes responsible for raising sourdough bread, not to mention making it more nutritious and delicious than bread made with commercial yeast. For starters, where do the fungi and bacteria in a sourdough starter come from? Are they in the water or the flour? Do they come from the baker’s hands? Or perhaps they’re just floating around in the foggy air, as the bakers of San Francisco firmly believe? This episode, Cynthia and Nicky go to Belgium with two researchers, fifteen bakers, and quite a few microbes for a three-day science experiment designed to answer this question once and for all. Listen in for our exclusive scoop on the secrets of sourdough.
No one knows how or when humans first figured out that if you mixed mashed-up grains and water and let them sit for a while, you got a bubbling beige goo that you could use to make beer or raise bread. (No one even knows whether humans went for the booze or the bread first, although Nicky is firmly on Team Booze.) Historians and archaeologists speculate that the first bread would have been fluffy and spongey, something like the injera that is still eaten in Ethiopia today. Despite the microbes, it would likely have still been quite flat, because the fermented ground grain-and-water mix would have been cooked simply by pouring it on a rock—there’s evidence that humans were grinding sorghum, an African grain, long before pottery was invented in which to bake the shaped dough into a loaf.
Sourdough starters in the Puratos Sourdough Library. Photo by Nicola Twilley.
Karl de Smedt and Cynthia in the Sourdough Library at Puratos Center for Bread Flavour. Photo by Nicola Twilley.
But once Louis Pasteur explained yeast’s role in fermentation using his new compound microscope in the 1850s, sourdough’s popularity slumped. Sourdough was finicky, unreliable, and slow; commercial baker’s yeast, which was first sold by the Fleischmann brothers just eleven years after Pasteur first published his discoveries, worked well enough, and it provided the same rapid results every time. By the 1960s, sourdough had all but been forgotten. In this episode, we trace its revival, but also reveal how science, which initially gave us boring baker’s yeast, is now uncovering the secrets of sourdough.
Scientists Anne Madden and Rob Dunn (1) introducing the experiment, (2) swabbing the sourdough starters, (3) swabbing baker Paul Barker’s hands, and (4) peeking at the unbaked loaves. Photos by Nicola Twilley.
Microbiologists Rob Dunn and Anne Madden allowed us to accompany them to Belgium for their ground-breaking experiment to discover where the microbes in a sourdough culture come from. While there, we visit the world’s first and only Sourdough Library, learn how the microbes in sourdough improves the texture, flavor, and nutritional quality of bread, and eat our body weight in baked goods. And then, the results! Why do bakers have “sourdough paws”? What is so special about Australian starters? And where do all those microbes actually come from? All that and more this episode: listen in now!
Rob Dunn’s lab at North Carolina State University aims “to tell the stories of the small species–whether on our bodies, under our beds or in our backyards–humans interact with every day but tend to ignore.” Their Sourdough Project is coordinated and led by Anne Madden, a post-doc in Dunn’s lab, and involves collaborations with Gastropod’s own in-house microbiologist, Ben Wolfe, at Tufts University, as well as many others. They have already posted the results of their big sourdough sampling project online here.
Puratos & the Sourdough Library
Puratos is a bakery supply company headquartered in Belgium. It generously hosted this three-day sourdough experiment at its Center for Bread Flavour in the small town of Sankt Vith, near Liège. Karl de Smedt, who also manages training and communications at Puratos, launched the Puratos Sourdough Library in 2013: it’s the largest collection of of sourdough starter microbial diversity in the world. You can take a virtual tour on the Puratos website here.
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(1) Bakers baking using the same ingredients and protocol, (2) their very different finished loaves, (3) playtime! Hakan’s cheesy egg bread gets papped, (4) more recreational baking: Hakan shows off a fancy seed design. Photos by Nicola Twilley.
For a transcript of the show, please click here. Please note that the transcript is provided as a courtesy and may contain errors.
Rank #13: Kombucha Culture
If you haven’t tasted kombucha yet, you probably will soon. The sour-sweet, fizzy, fermented tea is becoming ubiquitous in trendy cafes, workplaces, and health food stores across America. Where did it come from, and how did it get so popular? And what in the world is the slimy, beige blob that produces it? From German POWs to Lindsey Lohan to a kombucha zoo at Tufts University, this episode explores the history and science of summer’s hottest drink.
Kombucha’s origins—like almost everything about the drink—are a combination of myth and mystery. According to Tufts University microbiologist Ben Wolfe, all we know is “it was originally produced in parts of China, as well as what is now Russia.” Other countries, including Korea and Tibet, have their own kombucha creation stories. Though the exact date and location in which it was first brewed remains obscure, it seems clear that kombucha arose in the Far East, where tea has been popular for thousands of years.
That doesn’t explain how kombucha traveled west. But, by translating a little-known paper published in the Deutscher Apotheker Verlag (a German scientific journal) in 1930, Gastropod managed to trace the arrival of the “Indian tea fungus,” as the author called it, to Europe following World War I, when it was brought home by German POWs who had been held in Russia. Still, it wasn’t until 1990s Los Angeles that kombucha became a commercial success in the U.S., fueled first by the AIDS epidemic, and later by a growing interest in probiotics and gut health.
In the episode, listeners meet The Blob (also known as a SCOBY or mother): a fibrous, slippery mat of yeast and bacteria that ferments sugary tea into kombucha. Gastropod co-hosts Cynthia and Nicky bring segments of their own home-brew blobs to Wolfe’s lab, contributing to what may well be the world’s largest collection of kombucha cultures. (Wolfe created his kombucha zoo by scouring Etsy for samples from around the United States.) The hosts’ cultures go head-to-head, competing under the microscope and under the scientists’ noses for the healthiest, most fragrant, and all-round best kombucha. Along the way, Wolfe explores the fascinating microbiology behind each culture’s unique flavor and behavior.
While kombucha fans have long promoted the drink as a cure-all, listeners may be disappointed to learn that there’s little science supporting such health claims, though Wolfe does suggest a potential mechanism through which fermented tea might have a positive impact on the gut microbiome. But, even though it likely doesn’t hold the secret to eternal life, Wolfe is hoping his kombucha collection will help answer much more fundamental questions about microbial life. Along the way, he may even discover how to engineer the perfect blob.
Cynthia records Ben pipetting.
Listen in now to discover the bizarre history and fascinating science of kombucha, as well to find out whether Nicky or Cynthia’s blob won the Great Gastropod Co-Host Kombucha Smackdown.
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Rank #14: Green Gold: Our Love Affair with Olive Oil
Olive oil is not what you think it is. According to Tom Mueller, author of Extra Virginity: The Sublime and Scandalous World of Olive Oil, an olive is a stone fruit like a plum or cherry—meaning that the green-gold liquid we extract from it “is, quite literally, fruit juice.” And, while we’re blowing your minds, have you ever stopped to wonder what “Extra Virgin” means? “It’s like extra dead or semi-pregnant,” Mueller said. “I mean, it doesn’t make any sense at all.” This episode we visit two groves—one in the Old World, one in the New—to get to the bottom of olive oil’s many mysteries. Listen in this episode as we find out why the ancient Romans rubbed it all over their bodies, and whether the olive oil on our kitchen counters really is what it says on the label.
Olive oil’s original home lies along the shores of the Mediterranean, where its wild ancestor, the oleaster, can still be found today. Somehow, people realized that the bitter berry from these hardy trees tasted excellent when brined in salt and, even better, could be crushed to produce a liquid fat that was not only delicious but, Mueller says, burns as hot as benzene and has twice the caloric content of carbon. By the seventh century BCE, olive oil production was taking place at industrial scale: olive presses excavated at Ekron, in modern-day Israel, were capable of producing 500,000 liters of oil a year. The demand was equally enormous: olive oil powered lamps and preserved and enhanced food, and it was used an all-purpose medicine, a contraceptive—even an aphrodisiac. Olive oil was so critical to Greek and Roman culture that wars were fought over it and fortunes made, much like the petroleum sheikhs of today.
Olive trees at the Castello del Trebbio in Tuscany; olive oils (Frantoio single varietal, the Castello del Trebbio blend, and the Castello del Trebbio blend gone rancid) laid out for tasting in the castle courtyard. Photos by Nicola Twilley.
Today, olive oil is more popular in the kitchen than in a lamp, but it still enjoys a superior status to its fellow fats—particularly since the 1980s, when it began began to be promoted by medical researchers as a key component of the heart-healthy Mediterranean Diet. But all is not well in the olive groves. In Italy, millions of olives have already been killed by Xylella fastidiosa, an insect-borne pathogen that was detected in 2013. The disease can cause mature trees to die of thirst within two years. We speak to Rodrigo Almeida, a professor of environmental science at the University of California, Berkeley, to find out how worried we should be about the future of Italian olive oil. Meanwhile, olive oil fraud is rampant in general, but especially in the U.S., as profits from fraudulent oil can be more lucrative than dealing cocaine.
But fear not: we won’t leave you on this depressing note. Instead, olive oil growers Anna Casedei of the Castello del Trebbio in Tuscany, and Kathryn Tomajan and Robin Sloan of Fat Gold in Sunol, California, lead us through harvesting, milling, and, most importantly, tasting, in order to equip us to buy, use, and love olive oil nearly as much as they do. Listen in now, and then enjoy a big glug of oil over your veggies—heck, we won’t judge if you want to rub it on your skin, too!
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Kathryn and Robin’s Fat Gold
Kathryn Tomajan is an award-winning olive oil taster, miller, and consultant; her partner Robin Sloan is a novelist. Together, they decided to lease a small grove in California’s East Bay and make olive oil. This year is their very first harvest, and they are making their single-varietal oil available by subscription: get yours, and read about their adventures, here.
Anna’s Castello del Trebbio
Anna Casadei oversees roughly ten thousand olive trees at the Castello del Trebbio, her family estate in the hills outside Florence. In addition to growing olives and making oil, she serves on the Florence Chamber of Commerce as an official extra virgin olive oil taster. In case you happen to be traveling in the area, they do offer tours, as well as apartments for farm stays!
Toni Mazzaglia and Taste Florence
Toni Mazzaglia is the best. If you’re planning a trip to Italy, you need to take one of her amazing Taste Florence food tours. And, if you’re a journalist looking to report a story in Italy, Toni has seeming magical powers to make things work: you can reach her here. We can’t recommend her highly enough!
Rodrigo Almeida and Xylella fastidiosa
Rodrigo Almeida is a professor of environmental science at the University of California, Berkeley, much of whose work focuses on Xylella fastidiosa.
UC Davis Olive Oil Fraud Report
In 2010, UC Davis published this report into olive oil authenticity. Among their findings: sixty-nine percent of the extra virgin olive oil for sale on California supermarket shelves was not authentic.
Rank #15: The United States of Chinese Food
Wander into any town in the U.S., no matter how small and remote, and you’re likely to find at least one Chinese restaurant. In fact, there are more Chinese restaurants in America than McDonalds, KFC, and Burger King combined. And the food they serve is completely unlike anything you’ll find in China. In this episode of Gastropod, we ask one crucial question: why?
From the Gold Rush to MSG, via the scandalous story of gender-bending Chinese restaurants in 1920s New York City, this episode of Gastropod serves up a tasty buffet of American Chinese food. Grab your chopsticks and dive in!
Inspired by the new documentary “The Search for General Tso,” directed by Ian Cheney and co-produced by Jennifer 8. Lee, author of The Fortune Cookie Chronicles, Gastropod embarked on a quest of our own to untangle the curious history of Chinese food in America. Things got off to an unpromising start: in the nineteenth century, the first wave of Chinese immigrants was greeted with deep suspicion and hostility by Americans of European descent. This mistrust extended to their food: the Chinese ate rice with sticks and, many believed, hid all manner of unpleasant meats in their dishes. A perfectly serious 1883 article in The New York Times began with the question: “Do the Chinese eat rats?”
Stereoscopic view of the interior of a Chinese restaurant in San Francisco, in the 1880s, from the collection of the New York Public Library. Below, Chinese restaurant menu from 1904, from the collection of the New York Public Library.
And yet, between 1870 and 1920, the number of Chinese restaurant workers in America grew from 164 to 11,438. Why did Chinese immigrants abandon mining and manual labor to open restaurants—and, more importantly, how on Earth did these new chefs convince white Americans to eat their food? We speak with researcher Heather Lee, who discusses the loophole in American immigration law that unintentionally incentivized the Chinese to become culinary entrepreneurs. Meanwhile, with Jenny 8. Lee we explore the murky origins of chop suey, the dish that took America by storm, but one she considers “the best culinary joke played by one culture on another.”
By the early twentieth century, Chinese food was well on its way to becoming the most popular ethnic food in America. The same adaptive strategies that allowed them to bypass the racist Chinese Exclusion Act and reinvent their cuisine for the American palate continued to serve Chinese restaurateurs well throughout the twentieth century. In this episode, Heather Lee introduces us to the “dine & dances” of the 1920s—exotic, late-night Chinese restaurants in New York City where young people could experiment with new gender roles. Outside the context of their own cultural expectations, women flirted and couples kissed in public, shocking the city’s anti-vice inspectors.
American Chinese food’s biggest headache arrived in the 1960s, with a letter to the New England Medical Journal blaming monosodium glutamate for a range of unpleasant symptoms. But is MSG actually harmful? We dig into the science behind “Chinese restaurant syndrome” to try to put the myth to rest for once and for all.
Listen in to this episode of Gastropod for all this and more, including the economics of the Chinese all-you-can-eat buffet and the curious regional and global variations on Chinese cuisine. Just don’t blame us if you end up ordering take-out tonight…
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The Search for General Tso
The movie that inspired this episode of Gastropod! Ian Cheney’s documentary (co-produced by Gastropod guest Jenny 8. Lee) is a funny and fascinating look at the story behind the most famous American Chinese dish of all. It was released earlier this year and is now available on Netflix, iTunes, The Search for General Tso">Amazon, etc. Be sure to check it out!
The Fortune Cookie Chronicles
Guest Jennifer 8. Lee’s 2008 book, The Fortune Cookie Chronicles: Adventures in the World of Chinese Food">The Fortune Cookie Chronicles, explores the many mysteries of American Chinese food—who invented fortune cookies? why is Chinese food so popular with American Jews?—but also tells the stories and struggles of the immigrants who cook, serve, and deliver it.
Heather Lee is a postdoctoral researcher at MIT, working on a book about the Chinese immigrant experience, and Chinese restaurants in particular, in America. A fascinating talk she gave at MIT about her research on New York City’s “dine & dances” provided one of the inspirations for this episode. In 2016, she’ll be an assistant professor at NYU in Shanghai.
Jonathan Soma, MSG and the Brooklyn Brainery
With ice-cream episode guest Sarah Lohman, Jonathan Soma co-hosts the other MSG—the Masters of Social Gastronomy event series. He also runs the Brooklyn Brainery, and does lots of interesting things with data and code.
The Great Gastropod Raffle
This is your last chance to enter the Great Gastropod Raffle and win fabulous prizes—gorgeous Gastropod T-shirts, fascinating food books, and limited edition “Confused”-flavor Skittles. Donate $10 or more to support the show, and we’ll throw your name in the hat, to be drawn at the end of the month. (No donation necessary to enter, though, of course, we hope you will; email firstname.lastname@example.org to be entered without making a donation.)
Rank #16: The Good, The Bad, The Cilantro
On the surface, it’s just a leafy green herb. Its feathery fronds add a decorative note and a distinctive flavor to dishes across Latin America and Asia, from guacamole to phở. And yet cilantro is the most divisive herb in the kitchen, inspiring both deep dislike and equally deep devotion. What’s the history and science behind these strong reactions—and can cilantro disgust ever be overcome?
Some people (like Gastropod co-host Cynthia Graber) absolutely detest cilantro. From their very first taste of the humble herb, they find themselves repelled by what many consider a soapy, metallic, deeply off-putting flavor. These people are not shy about sharing their feelings: there are “I Hate Cilantro” websites, Facebook groups, and blogs. Somehow, cilantro inspires a degree of vociferous loathing that is unlike any other food.
And yet there are others (like co-host Nicola Twilley) who adore the herb. It adds what they consider a delightful green, herbal complexity to cuisines from Mexican to Thai to Indian. Billions of people around the world enjoy cilantro daily, and consider their guacamole, noodles, and soups nearly naked without it.
What is it that makes this herb a culinary essential for some and a culinary nemesis for others? In this episode of Gastropod, we speak with botanist Michael Balick to learn about the long culinary and medicinal history of the herb, whose recorded use dates back to the Babylonians. With scientist Charles Wysocki, we investigate the popular belief that cilantro hatred has a genetic basis by visiting the annual twin meet-up in Twinsburg, Ohio. And food scientist and author Harold McGee joins Gastropod to coach Cynthia through his recommended cilantro desensitization technique, by adding cilantro pesto to her daily diet.
This episode is introduced by best-selling author and marketing guru Seth Godin, a cilantro hater who suggested Cynthia become a guinea pig for cilantro conversion therapy, in his stead. But will Cynthia be able to choke down a daily dose of the green stuff? Will she end up tolerating—even perhaps liking—the herb by the end of the week? Whether you’re a lover or a hater, listen in to find out the answer—and the history and science behind it.
Seth Godin is the cilantro hater who asked Gastropod to investigate the science and history behind this divisive herb. He’s also the author of 18 bestselling books on marketing, leadership, and the way ideas spread: the most recent is titled What To Do When It’s Your Turn. He writes one of the most popular blogs in the world.
Michael Balick is vice president for Botanical Science at the New York Botanical Garden, and author of Rodale’s Twenty-first Century Herbal: A Practical Guide for Healthy Living Using Nature’s Most Powerful Plants.
Harold McGee and the Cilantro Desensitization Pesto
Harold McGee writes about the chemistry of food and cooking, most famously in his book On Food and Cooking. His 2010 New York Times article titled “Cilantro Haters, It’s Not Your Fault” suggested making this Portuguese-inspired pesto as the first step in cilantro conversion therapy.
Washington Post, 1994
In her senior year of college, Cynthia and her roommate Melissa Strecker gleefully brandished this Washington Post article, “Has a Nation Taken Leaf of Its Senses?” to demonstrate they were not alone in their cilantro dislike. This was the first instance Cynthia had seen of a public display of cilantro loathing, one to which she felt an immediate kinship.
An anti-cilantro community.
Charles Wysocki is an emeritus member of the Monell Chemical Senses Center whose research explores individual variation in smell perception as well as human pheromones. His 2012 paper, “Genetic Analysis of Chemosensory Traits in Human Twins,” identified the genetic associations common to cilantro haters.
The world’s largest gathering of twins takes place each year in Twinsburg, Ohio.
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Rank #17: The Salt Wars
Salt is a magical substance. It reduces bitterness, enhances sweetness, boosts flavor, and preserves perishable foods. Without it, we would die: the human body can’t make sodium, but our nerves and muscles don’t work without it. It was considered rare until quite recently, so it’s hardly surprising that, throughout history, salt has been the engine behind empires and revolutions. Today, there’s a new battle in the salt wars, between those who think that we eat too much of it and it’s killing us—and those who think most of us are just fine. Join us for a serving of salt, seasoned with science, history, and a little politics.
One of salt’s many mysteries is how our ancestors first figured out that they needed it: unlike hunger or thirst, someone suffering a sodium deficiency doesn’t crave salt. What’s more, until humans began farming, we had no need to add salt to our diets—even today, Masai hunter-gatherers can get enough salt simply by drinking the blood of their livestock. But, however our need for salt was discovered, extracting it and trading it has shaped human history. From the very first brine wells in Sichuan province, China, to Mahatma Gandhi and the Indian independence movement, author Mark Kurlansky helps us trace the impact of salt through language, taxation, cuisine, and empire.
Cynthia and Nicky interviewing Don Tydeman at The Salt Cellar, Portsmouth, NH. Photo by Kathi Bahr.
Although salt was one of the world’s most valuable commodities for millennia, modern geology, technology, and food processing has made it cheap and ubiquitous. Globally, we each eat an average of 3,500 milligrams of sodium a day—a little more than a teaspoon and a half of salt. According to institutions such as the World Health Organization, the U.S. Centers for Disease Control, and the American Heart Association, that’s too much, and, if we want to avoid dying from cardiovascular disease, we need to reduce our consumption. But is that really true?
As the U.S. Food & Drug Administration prepares to issue new sodium reduction goals for food manufacturers, we dive into the contentious science of sodium to tease out what we do and don’t know about the connection between salt consumption and health. It’s a much more nuanced story than the constant refrain that we need to cut down would imply. So why is the U.S. government making policy if the scientific evidence isn’t conclusive? In a special collaboration with the podcast DecodeDC, we untangle what the FDA is doing, and why—and what that means to you, as a consumer. The draft guidance remains open for comment until August 31.
Finally, we come full circle and explore salt’s current culinary renaissance. From artisanal Icelandic lava salt to handmade hyper-local sea salt, we visit the enthusiasts who are restoring salt’s lost status and value.
Worried that you need to shake your salt habit? Curious about the merits of different gourmet salts? Mystified by the popularity of salt cod? Listen in this episode for answers to all these questions and more.
This episode is a special collaboration with our friends at DecodeDC, the podcast that helps make sense of people, policies, and politics in the nation’s capital. To explain what the U.S. Food and Drug Administration is doing with regard to salt and why, host Jimmy Williams spoke to Robert Brackett, vice president and director of the Institute of Food Safety and Health (IFSH) at Illinois Institute of Technology, and former director of the FDA Center for Food Safety and Applied Nutrition. Listen to their conversation here.
Mark Kurlansky is the author of twenty-nine books, including Salt: A World History. His most recent book, Paper: Paging Through History, explores the ways in which this seemingly simple technology has shaped the world.
We spoke with a number of scientists to help unravel the competing arguments for and against salt reduction. This explainer by Julia Belluz for Vox provides a good overview of the logic behind salt reduction targets, and the evidence thus far. This 2013 Institute of Medicine report on the subject is a more in-depth read that concludes that there is not sufficient evidence to set an upper limit for sodium consumption. This Politico analysis by Helena Bottemiller looks at the conflicts between the food industry, policy makers, and scientists on the subject of salt.
Michael (Micky) Alderman, professor of epidemiology and medicine at Albert Einstein College of Medicine, is a specialist in hypertension who has authored many papers on the subject, including a 2014 meta-analysis that found that consuming less than 2,600 or more than 4,900 milligrams of sodium per day was associated with increased mortality compared to the ninety percent of the population who consume between 2,600 and 4,900 mg/day. Andrew Mente, an epidemiologist at McMaster University, co-authored a recent study in The Lancet in July 2016, in which he and his colleagues concluded that there was no benefit to reducing sodium for people with normal blood pressure.
Sandra Jackson, an epidemiologist with the U.S. Centers for Disease Control, published a study showing how much sodium Americans consume in January 2016. More information on the CDC’s sodium reduction initiatives can be found online here. Nancy Cook, an epidemiologist and professor of medicine at Harvard, leads the Trials of Hypertension Prevention (TOHP) Follow-up Study, focusing on the long-term effects of weight loss and sodium reduction interventions on subsequent cardiovascular disease. Her findings show that for a population with hypertension, there are no risks from low sodium consumption and, in a paper currently in press, that lowering sodium consumption is associated with a reduction in mortality.
Gary Beauchamp, emeritus director and president of the Monell Chemical Senses Center, is an expert on salt taste perception.
The FDA’s draft guidance for industry on sodium reduction was issued in June 2016, and will remain open for comment through August 31, 2016. (UPDATE: The comment period has now been extended until October 17, apparently “to give industry more time to respond.”)
Husband and wife team Don and Judit Tydeman opened The Salt Cellar, a store devoted entirely to salt, in Portsmouth, New Hampshire, in 2011. They now have a second location in Portland, Maine.
Chef Marc Sheehan spoke to us about the process and concept behind making his own salt, which he uses to finish dishes at his restaurant, Loyal Nine, in Cambridge, Mass.
Extra Goodies for Sustaining Supporters
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Rank #18: The Scoop on Ice Cream
It’s one of the most complex food products you’ll ever consume: a thermodynamic miracle that contains all three states of matter—solid, liquid, and gas—at the same time. And yet no birthday party, beach trip, or Fourth of July celebration is complete without a scoop or two.
That’s right—in this episode of Gastropod, we serve up a big bowl of delicious ice cream, topped with the hot fudge sauce of history and a sprinkling of science. Grab your spoons and join us as we bust ice-cream origin myths, dig into the science behind brain freeze, and track down a chunk of pricey whale poo in order to recreate the earliest published ice cream recipe.
Colder Than Ice
Contrary to popular myth, ice cream was not brought to Italy from China by Marco Polo, and then introduced to France by Catherine de Medici. In fact, it is a delicious love-child, born of the union between a culinary tradition of custards and burnt creams in medieval Northern Europe, and the fruity, floral, sherbets (sharbat in Persian) that were typically served over ice as a refreshing drink in the Middle East.
For millennia, humankind has gathered and stored natural ice and snow in order to preserve food and chill drinks—snow was sold in the markets of Athens in the fifth century, and wealthy Romans, inspired by Middle Eastern sherbets, recklessly disobeyed the medical advice of their day by mixing ice chips to their wine. But simply adding ice is not enough to freeze sherbet into sorbet: to do that required the creation of a substance that was colder than ice.
Early ice creams were formed into elaborate molds and painted to create trompe l’oeil dinner displays. This image comes from Ivan Day, a food historian and teacher who tracked down the first published ice cream recipe and who owns an incredible collection of antique ice cream molds.
That scientific breakthrough occurred in Naples, when Giambattista della Porta, a Renaissance-era polymath who had already invented a new cryptographic system and perfected the camera obscura, decided to turn his attention to the science of freezing. By combining snow with saltpeter (potassium nitrate, which was manufactured in bulk as an explosive for military use) in a bucket, he managed to make a mixture that was cold enough that a sealed bottle of water submerged in it would turn to ice. It worked because the saltpeter draws the frozen water in the snow out from its crystalline structure, causing it to melt. The phase change from solid to liquid requires energy in the form of heat, lowering the temperature of the resulting salty slush to about 0ºF—plenty cold enough to freeze water.
Della Porta immediately tried his new technique out on a decanter of wine, which didn’t freeze solid because of ethanol’s low freezing point. Nonetheless, according to food writer Jeri Quinzio, his wine slushies were “a big hit on Italian banquet tables” of the late 1500s and early 1600s. By the 1620s, however, scientists and then cooks had worked out that della Porta’s technique worked even better using salt, rather than saltpeter, and that 0ºF was cold enough to freeze the perfumed sherbets of the Middle East into the first sorbets.
Before too long, an anonymous confectioner had the bright idea to see whether the same trick worked with a custard mix—and ice cream was born. The first recorded recipe comes from an unpublished cookbook written by an Englishwoman, Lady Anne Fanshawe, in 1665. Quinzio speculates that Fanshawe first encountered what she called “Icy Cream” in Spain, where her husband served as ambassador. In her recipe, she suggests flavoring it with orange-flower water (in a nod to its Middle Eastern roots), mace (a cousin of nutmeg), or ambergris—a greasy, odorous lump of fossilized squid beaks, mucus, and compacted fecal matter formed in the intestines of some sperm whales that, for thousands of years, has been prized as a perfume, spice, and even medicine. In the episode, historical gastronomist Sarah Lohman scored some wildly expensive and technically illegal ambergris in order to recreate Lady Anne Fanshawe’s ice cream; listen in to hear our verdict on the taste.
Historical gastronomist Sarah Lohman eats ambergris ice cream out of a reconstruction of the original ice cream cone.
Let Them Eat Ice Cream
Those early ice creams were a luxury item, found only on the tables of the aristocracy. Its journey to becoming America’s favorite dessert involved several more steps, including the repeal of heavy salt taxes, the huge reduction in the price of sugar brought about by the Atlantic slave trade, and even the French Revolution—as their aristocratic masters met the guillotine, fancy confectioners spread out across Europe, bringing the secrets of ice cream-making with them. Many opened cafes and restaurants, making ice cream accessible to the masses.
But the real breakthrough in the democratization of ice cream came thanks to Frederick Tudor, a Bostonian who had the brilliant idea of turning New England’s wealth of natural ice into a business. His first shipment set sail from Boston harbor in February 1806, bound for Martinique. Amazingly, a fair amount of his ice survived the journey—but upon arrival at the port of St. Pierre, Tudor encountered another challenge. There were no ice houses in Martinique, and the locals had no idea what to do with the lumps of melting ice that this peculiar American was trying to sell them. In desperation, Tudor used a large portion of his cargo to make ice cream—which was a huge hit, earning him the equivalent of $30,000 today.
By the mid-1800s, Tudor had perfected the art of harvesting, storing, and shipping ice, and the resulting economies of scale made it affordable for the majority of Americans. Meanwhile, in Philadelphia, a woman named Nancy Johnson took the next great leap in ice cream technology, by inventing the first hand-cranked ice cream-maker. Previously, making ice cream was a tedious and fiddly process that involved fishing the pot of custard out of the bucket of freezing brine at regular intervals during the freezing process, in order to pry off the lid and stir it. Johnson’s patented device had a crank on the outside of the barrel, attached to a churn on the inside, with the salty slush enclosed in a slim gap between the two. The ability to churn the ice cream without removing it from the bucket was a significant step forward in both convenience and quality, allowing for a smoother texture, and Johnson’s machine quickly caught on. With the addition of a motor to power the churn and an even colder chemical inside the barrel walls, today’s ice cream-makers still work exactly the same way.
Traditional ice cream-maker from 1768, before Nancy Johnson’s labor-saving invention, via.
The New Golden Age
In the twentieth century, ice cream had its ups, including the invention of the popsicle and the Eskimo Pie, but also its downs, as industrial cost-cutting drove a reduction in the quality of ingredients. Today, however, ice cream is entering a new golden age. A new generation of artisanal ice cream-makers is experimenting with adventurous and unusual flavor combinations: listeners wrote in to tell us about poutine-flavored ice cream in Portland, chocolate-chile in Boston, and sweet corn with blackberry swirl in Cleveland. Meanwhile, scientists are developing an entirely new vocabulary of ice cream textures, from fizzy to stretchy. Listen to this episode to learn more—and to get to the bottom of the mystery of the first ice cream cone, as well as learn how ice cream escaped the confines of summer to become a year-round treat (hint: it involves breakfast cereal). And don’t forget to enter the Great Gastropod Raffle—with a $10 donation, you will be entered to win all sorts of fabulous prizes!
Of Sugar and Snow
Writer Jeri Quinzio’s Of Sugar and Snow is a fascinating journey through ice cream’s history. We wanted to include many, many more of the stories she recounts, including why the term Hokey Pokey might have come from Italian ice cream street vendors, and how the U.S. Armed Forces got into the ice cream business during WWII. You’ll just have to read her book to find out.
Four Pounds Flour
Historical gastronomist Sarah Lohman regularly updates her amazing blog, Four Pounds Flour, with her adventures in recreating recipes from the past. She also co-hosts a fun event series all about the science and history of food called Masters of Social Gastronomy, or MSG, which, for those of you who don’t live in New York City, can also be enjoyed in podcast form.
The Science of Ice Cream
As Chris Clarke, author of the Science of Ice Cream, explained in this episode, it took hundreds of years for scientists to understand why ice cream is so complex. (His book is the textbook on ice cream science.) Still, the basic ingredients and technique for making ice cream haven’t evolved much since the 1600s, when spiced and scented custards first met a frozen slushy bath. But today, scientists are thinking outside of the mold to develop new and exciting textures. John Brisson, a mechanical engineer at MIT, worked with his former PhD student Teresa Baker Peters to develop fizzy ice cream (though it hasn’t yet been commercialized—we’re waiting!). And scientists Arielle Johnson and Kent Kirschenbaum developed a new way to make stretchy ice cream that still melts in your mouth; they were inspired by the traditional Turkish ice cream called salep dondurma, which is made using the roots of an endangered orchid. Johnson and Kirshenbaum’s version used konjac, a much more common plant found in Japanese dishes such as sukiyaki. The resulting ice cream is apparently “both ‘slightly sweet with a nutty flavor similar to dried milk powder’ and ‘capable of being used as a jump rope.'”
From Teresa Baker Peters’ 2006 PhD thesis on fizzy ice cream: “Carbon dioxide flash-freezing applied to ice cream production.”
Ice cream headaches feel like a short, sharp shock to the brain. But until three years ago, scientists weren’t sure quite why they happened. In 2012, a group of researchers wanted to study migraine headaches and so turned to brain freeze as a model. They published this study that finally explains the science behind brain freeze.
Lady Anne Fanshawe’s Icy Cream
Lady Anne Fanshawe published the first known recipe for ice cream, which Sarah Lohman and Nicky tested for the show. Here’s her recipe, so you can try it at home. Notice she fails to mention that you need to add ice to the salt—did she forget, or did she not know the true secret of ice cream?
Ambergris seems like a strange substance to flavor food and use as a perfume, as it is created when sperm whales get squid beaks stuck in their intestines. They eventually pass the irritating lump, and it then cures in the hot sun and saltwater before washing up on a beach somewhere to make somebody’s fortune. Read Cynthia’s article in Scientific American for more unusual ambergris facts.
Frederick Tudor and the Frozen-Water Trade
The rise and fall of the natural ice harvest makes for a fascinating story. While you wait for Nicky’s magnum opus (!) on refrigration, check out Gavin Weightman’s excellent book on Frederick Tudor’s life and work, The Frozen-Water Trade.
The Great Gastropod Raffle
You can also win a couple of different ice cream history books, including Jeri Quinzio’s; Dave Arnold’s stunning book, Liquid Intelligence, from our cocktail episode; and even some packages of the special edition “Confused” Skittles that starred in our flavor episode, which Nicky smuggled over from England. Each ten dollar gift to support our work buys you one raffle ticket (we’ll enter multiple tickets for you if you donate more than $10)—make a donation here to win! (No donation necessary to enter, though, of course, we hope you will; email email@example.com to throw your name in the hat without a donation.)
Cynthia models a Gastropod T-shirt.
Rank #19: The Curry Chronicles
Curry is, supposedly, Indian. But there is no such word in any of the country’s many official languages—and no Indian would use the term to describe their own food. So what is curry? This episode takes us to India, Britain, and Japan on a quest to understand how a variety of spicy, saucy dishes ended up being lumped together under one name—and then transformed into something completely different as they were transported around the world. From a post-pub vindaloo in Leeds to comforting kare raisu in Kyoto, we explore the stories and flavors of curry—a dish that’s from nowhere and yet eaten nearly everywhere.
According to Lizzie Collingham, food historian and author of Curry: A Tale of Cooks and Conquerors, to trace the origins of curry, we need to go back to when the Portuguese first set up shop in Goa, in the early 1500s. “And they’d say, Oooh, what are you eating?” said Collingham, “And the Indians replied using a word like khari or caril.” At the time, Collingham explained, those words likely referred to a particular spice blend, as well as the finished dish it was used in; the same words are still in use, but they now mean sauce or gravy. Today, that’s Raghavan Iyer’s definition: he authored a doorstop of a cookbook called 660 Curries, and he uses “curry” to refer to “anything that has a sauce or gravy—it can be with or without spices.”
But how did India’s many and varied ragouts and stews all come to be known as curry? For that, we have to look to the British. With Collingham’s help, Gastropod teases out the origins of dishes such as biryani and vindaloo, tracing their journey from complex, regional specialties to simplified, curryhouse classics, thanks to a combination of colonialism, empire, and immigrant entrepreneurialism. Along the way, we pinpoint the rise of curry powder, trace curry’s global diaspora, and spend some time with Mr. Bean. We even get to the bottom of why the Japanese—a nation whose cuisine is defined by its exquisite aesthetic—love their own brown, gloppy version. Listen in now to discover the world of curry.
Lizzie Collingham’s Curry: A Tale of Cooks and Conquerors
Lizzie Collingham is a historian and author of a number of books, including, most recently, The Hungry Empire: How Britain’s Quest for Food Shaped the Modern World. Her 2006 book, Curry: A Tale of Cooks and Conquerors, is a deeply enjoyable read, and even contains a few historical recipes, for the adventurous.
Takashi Morieda is a photojournalist based in Tokyo. He’s written extensively about Japanese curry culture, including this essay, titled “The Unlikely Love Affair with Curry and Rice.”
Vindaloo is a song by British prank art collective/band Fat Les, whose members are Blur bassist Alex James, actor Keith Allen, and artist Damien Hirst. It was released in 1998, in the run up to the football World Cup, as a parody of football chants. It has been stuck in Nicky’s head throughout the time we’ve been working on this episode.
For your viewing pleasure: curry scenes from Only Fools and Horses, Gavin and Stacey, Peep Show and Auf Wiedersehen, Pet. Astonishingly, a British man (Vern Slade from Newcastle) actually had Smithy’s curry takeaway order from Gavin and Stacey tattooed on his arm while on a lad’s holiday. Also for your enjoyment: Rowan Atkinson’s sketch about drunk Englishmen in an Indian restaurant, and the cast of Goodness Gracious Me “going out for an English.”
What’s a Ruby?
In the episode, Nicky says that long pepper is not related to black pepper. This is incorrect: they are both in the Piperaceae family, and are close relatives. We apologize for the mistake!
Rank #20: The End of the Calorie
For most of us, the calorie is just a number on the back of the packet or on the display at the gym. But what is it, exactly? And how did we end up with this one unit with which to measure our food? Is a calorie the same no matter what type of food it comes from? And is one calorie for you exactly the same as one calorie for me? To find out, we visit the special rooms scientists use to measure how many calories we burn, and the labs where researchers are discovering that the calorie is broken. And we pose the question: If not the calorie, then what?
The calorie seems to be an obvious measurement for food. But, in fact, it took hundreds of years and thousands of experiments to nail down what exactly the calorie means, both as a measurement of the food itself (that is, how much energy is contained in the form of a cheeseburger) and a measurement of consumption (how much energy we cheeseburger-eating humans burn as we go about our daily lives). With assistance from nutritionist Marion Nestle, author of Why Calories Count: From science to politics, we trace the calorie’s earliest history, from an obsessive-compulsive Italian who invented a special chair with which to measure everything he ate, drank, and excreted over a thirty-year period, to the French chemist who put a guinea pig in a coffee urn to measure how much heat it gave off. Then we travel to the USDA laboratories in Beltsville, Maryland, to check out the way scientists measure calories today: by putting people in tricked-out walk-in coolers and freeze-drying their feces.
IMAGE: (Left) Santorio Sanctorius’s weighing chair. (Right) Lavoisier and Laplace’s Ice Calorimeter (Diucênio Rangel/Nature Education).
While we’re in Beltsville, we also learn about intriguing new USDA studies that have found that, for some foods, the calorie counts on the label are off by double-digit percentages. Following this trail, we end up at Harvard, talking to anthropologist Richard Wrangham about the ways humans have learned to change the number of calories we get from our food by cooking it. And we dive into the differences in how people process calories by visiting microbiologist Peter Turnbaugh at UCSF, who points us to dramatic new research demonstrating the effect the tiny creatures in our gut have on the amount of calories we absorb. The University of Alberta’s David Wishart offers us a glimpse of the future, in which truly personalized nutrition advice will evolve from the emerging science of how the chemicals in our bodies interact with all the different chemicals in the food we eat. And Susan Roberts, director of the energy metabolism laboratory at the Tufts USDA nutrition center, suggests an alternative unit as a replacement for the traditional calorie.
Listen for all this and more, and then tell us what you think of the calorie. Do you find calorie labels useful, or is counting calories the bane of your life? Let us know!
David Baer and Bill Rumpler both work at the Food Components and Health Laboratory at the USDA-ARS headquarters, in Beltsville, Maryland. Check out Baer and his colleagues’ papers on the difference between the calories on the label and those our bodies can extract for almonds and walnuts.
Richard Wrangham’s Cooking Research
Calories and the Gut Microbiome
Peter Turnbaugh’s lab at the University of California, San Francisco, promises “better living through gut microbes.” In our conversation with him, we discussed this study on the effects that transplanting gut microbes from lean and obese twins had on the weight of mice. Further examples of the impact of microbes on energy balance can be found in this paper on one woman’s weight gain following a fecal transplant, and this paper on how risperidone is associated with altered gut microbiota and weight gain.
David Wishart and Metabolomics
David Wishart’s research group is based at the University of Alberta. You can check out the Human Metabolome Project Database online here. And the Israeli study on personalized nutrition based on individual glycemic responses is available online here.
Susan B. Roberts is the creator of the satiety-based “iDiet.” She has also done extensive research into the accuracy of calorie counts on menu labels. David Ludwig’s book, Always Hungry?, also proposes measuring foods based on their satiety score. Adam Drenowksi’s Nutrient-Rich Food Index is explained here.
Why the Calorie is Broken
We wrote a feature article for Mosaic, the online publication of the Wellcome Trust, to accompany this episode. You can read it online here.
The Chemical Definition of the Calorie
In the episode, we say that a calorie is the amount of heat energy needed to raise the temperature of one gram of water by one degree centigrade, from 14.5º to 15.5º, at one unit of atmospheric pressure. This is accurate, but it is misleading, because throughout the rest of the episode, we are discussing a different kind of calorie—the kilocalorie, which is the amount of heat energy needed to raise the temperature of one kilogram of water by one degree centigrade. The kilocalorie is the number we see on our food labels and recommended daily allowances, but no one other than chemists actually calls it the kilocalorie. Instead, it has been shortened to “calorie” on labels and in everyday usage. Throughout our episode, we follow common practice by calling a kilocalorie a calorie, but then we mistakenly gave the definition of a true calorie without noting the difference. We apologize for any confusion!