Finally, Gastropod is tackling gastropods! In this episode, Cynthia visits one of America’s first and only snail farms.

Though Gastropod is, as regular listeners know, a podcast about the science and history of all things gastronomical, we do share a name with Gastropoda, the taxonomic class that includes slugs and snails. And, as it turns out, the history and science of heliciculture, or snail farming, is completely fascinating.

IMAGE: Snail pen at Little Grey Farms escargotière, Quilcene, Washington. Photograph by Ric Brewer.

Join Cynthia on a trip to rural Washington State to learn how to raise snails and whether fresh and vacuum-packed taste any less rubbery than canned. Plus, you’ll hear about the earliest evidence for human snail consumption, how the Romans fattened theirs up, and all about the bizarre world of snail sex.

IMAGE: Snails in Little Grey Farms’ Seattle warehouse. Photograph by Ric Brewer.

And, when you’ve listened, visit Gastropod for all kinds of links, photos, and even a snail orgy caught on home movie.

DNA: it’s the genetic information that makes plants and animals what we are. Most of the time when you hear about it in the context of food, it’s to do with breeding. But in this short episode of Gastropod, we bring you two DNA detective stories that show how genetic analysis can rewrite the history of agriculture and fight food fraud—at least some of the time.

Listen now to hear how preserved DNA from an underwater site off the coast of Britain is helping paint a picture of how hunter gatherers in Northern Europe might first have experienced the wonders of agriculture, by trading kernels of exotic, domesticated Near Eastern wheat over long distances.

IMAGE: The Gastropod special, photographed by its creator, Chef Clare Anne O’Keefe.

We’ll also explore DNA’s role in some controversial accusations of food fraud and introduce you to the mysterious publication that defines the official standards of identity for food ingredients. And, finally, we squeeze in a short trip to Dublin’s Science Gallery, to talk to chef Clare Anne O’Keefe about a dish that was entirely inspired by Gastropod!

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 flavours 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. Unfortunately, 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.

Rind microbes from a Colston Bassett Stilton. Photograph courtesy of Benjamin E. Wolfe.

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 flavour,” 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.

Ben Wolfe examining his in-vitro cheeses for signs of life. Photograph by Nicola Twilley.

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 colour.

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 colour, 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.

Penicillium camemberti growing in a petri dish in Ben Wolfe’s lab. Photograph by Nicola Twilley.

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!

Step away from the French fries—and even from that bag of pre-washed mixed greens lurking in the crisper drawer. It’s time to reconsider the potato and up your salad game.

In this episode of Gastropod, Cynthia and Nicky talk to science writer Ferris Jabr about the chestnut-flavored, gemstone-hued potatoes he discovered in Peru, as well as the plant breeders working to expand American potato choices beyond the Russet Burbank and Yukon Gold.

Plus we meet wild gardener Stephen Barstow, whose gorgeous megasalads include 537 different plants, to talk about ancient Norwegian rooftop onion gardens and the weedy origins of borscht. If you thought you knew your veggies, think again—and listen in!

In 1900, the average dairy cow in America produced 424 gallons of milk each year. By 2000, that figure had more than quadrupled, to 2,116 gallons.

In this episode of Gastropod, we explore the incredible science that transformed the American cow into a milk machine—but we also uncover the disturbing history of prejudice and animal cruelty that accompanied it.

Along the way, we’ll introduce you to the insane logic of the Lifetime Cheese Merit algorithm and the surreal bull trials of the 1920s. This is the untold story behind that most wholesome and quotidian of beverages: milk. Prepare to be horrified and amazed in equal measure.

BREEDING A BETTER BULL

Something extremely bizarre took place in the early decades of the twentieth century, inspired by a confluence of trends. Scientists had recently developed a deeper understanding of genetics and inherited traits; at the same time, the very first eugenics policies were being enacted in the United States. And, as the population grew, the public wanted cheaper meat and milk. As a result, in the 1920s, the USDA encouraged rural communities around the U.S. to put bulls on the witness stand—to hold a legal trial, complete with lawyers and witnesses and a watching public—to determine whether the bull was fit to breed.

Livestock breeding was a normal part of American life at the dawn of the twentieth century, according to historian Gabriel Rosenberg. The U.S., he told Gastropod, was “still largely a rural and agricultural society,” and farm animals—and thus some more-or-less scientific forms of selective breeding—were ubiquitous in American life.

Meanwhile, the eugenics movement was on the rise. Founded by Charles Darwin’s cousin, Francis Galton, eugenics held that the human race could improve itself by guided evolution—which meant that criminals, the mentally ill, and others of “inferior stock” should not be allowed to procreate and pass on their defective genes. America led the way, passing the first eugenic policies in the world. By the Second World War, twenty-nine states had passed legislation that empowered officials to forcibly sterilize “unfit” individuals.

A scrub sire, pictured in the USDA’s pamphlet, “From Scrubs to Quality Stock.” The caption reads: “There is seldom any uniformity in scrub stock. About the only things they have in common are 4 legs, 2 horns, a hide, and a tail.”

A “Better Sires: Better Stock” accredited dairy herd.

Combine the growing population, the desire for cheap meat and milk, and the increasing popularity of eugenics, and the result, Rosenberg said, was the “Better Sires: Better Stock” program, launched by the USDA in 1919. In an accompanying essay, “Harnessing Heredity to Improve the Nation’s Live Stock,” the USDA’s Bureau of Animal Industry proclaimed that, each year, “a round billion dollars is lost because heredity has been permitted to work with too little control.” The implication: humans needed to take control—and stop letting inferior or “scrub” bulls reproduce!

HEAR YE! HEAR YE! WELCOME TO THE COURT OF BOVINE JUSTICE

The “Better Sires: Better Stock” campaign included a variety of elements to encourage farmers to mate “purebred” rather than “scrub” or “degenerate” sires with their female animals. Anyone who pledged to only use purebred stock to expand their herd was awarded a handsome certificate. USDA field agents distributed pamphlets entitled “Runts and the Remedy” and “From Scrubs to Quality Stock,” packed with charts showing incremental increases of dollar value with each improved generation as well as testimonials from enrolled farmers.

The “Better Sires: Better Stock” certificate, awarded to farmers who pledged to use purebred rather than scrub bulls.

By far the most peculiar aspect of the campaign, however, came in 1924, when the USDA published its “Outline for Conducting a Scrub-Sire Trial.” This mimeographed pamphlet contained detailed instructions on how to hold a legal trial of a non-purebred bull, in order to publicly condemn it as unfit to reproduce.

The pamphlet calls for a cast of characters to include a judge, jury, attorneys, and witnesses for the prosecution and the defense, as well as a sheriff, who should “wear a large metal star and carry a gun,” and whose role, given the trial’s foregone conclusion, was “to have charge of the slaughter of the condemned scrub sire and to superintend the barbecue.”

The Order of Procedure, from the USDA’s “Outline for Conducting a Scrub-Sire Trial,” 1924.

In addition to an optional funeral oration for the scrub sire and detailed instructions regarding the barbecue or other refreshments (“bologna sandwiches, boiled wieners, or similar products related to bull meat” are recommended), the pamphlet also includes a script that begins with the immortal lines: “Hear ye! Hear ye! The honorable court of bovine justice of ___ County is now in session.”

The County’s case against the scrub bull is laid out: that he is a thief for consuming “valuable provender” while providing no value in return, that he is an “unworthy father,” and that his very existence is “detrimental to the progress and prosperity of the public at large.”

Several pages and roughly two hours later, the trial concludes with the following stage direction: “The bull is led away and a few moments later a shot is fired.”

The verdict (a foregone conclusion), from the USDA’s “Outline for Conducting a Scrub-Sire Trial,” 1924.

Within a month of publication, the USDA reported receiving more than 500 requests for its scrub-sire trial pamphlets. Across the country, the court of bovine justice was convened at county fairs, cattle auctions, and regional farmers’ association meetings, forming a popular and educational entertainment.

THE GENOMIC BULL

These bull trials may seem like a forgotten, bizarre, and ultimately amusing quirk of history, but, as Rosenberg reminded Gastropod, “they are talking about a lot more than just cattle genetics here.”

Indeed, the very same year—1924—that the USDA published its “Outline for Conducting a Scrub-Sire Trial,” the State of Virginia passed a Eugenical Sterilization Law. Immediately, Dr. Albert Sidney Priddy, Director of the Virginia State Colony for Epileptics and Feebleminded, filed a petition to sterilize Carrie Buck, an 18-year-old whom he claimed had a mental age of 9, and who had already given birth to a supposedly feeble-minded daughter (following a rape).

Buck’s case went all the way to the Supreme Court, with Justice Oliver Wendell Holmes, Jr., upholding the decision in a 1927 ruling that concluded: “Three generations of imbeciles are enough.” Historians estimate that more than 60,000 Americans were sterilized in the decades leading up to the Second World War, with many more persecuted under racist immigration laws and marriage restrictions.

Still from “When the Cows Come Home,” a USDA Extension film, c. 1935, extolling the benefits of livestock improvement. At one point, the voiceover intones: “Domestic animals are supposed to be the slaves of man, but the man who owns a low-producing, non-profitable herd has this idea reversed.” Via the Prelinger Archives.

Eugenics, with its philosophical kinship to Nazism, largely fell out of favor in the U.S. by World War II. But the ideas promoted in the bull trials—that humans can and should take increasing control of animal genetics in order to design the perfect milk machine—have gained ground throughout the past century, as breeding has become ever more technologically advanced.

As we discuss in this episode of Gastropod, the drive to improve dairy cattle through livestock breeding has led to huge innovations—in IVF, in genomics, and in big data analysis—as well as much more milk. But it has also continued, for better and for worse, to highlight the ethical problems that stem from this kind of techno-utopian approach to reproduction.

Listen now to find out more about the bull trials of the 1920s and meet the most valuable bull in the world, as we explore the history and the high-tech genomic science behind livestock breeding today. Along the way, we tease out its larger, thought-provoking, and frequently deeply troubling implications for animal welfare and society in general.

Have you ever wondered how to avoid sandwich sogginess, what scented soap to pair with your restaurant order, and whether airplane food can be made to taste of anything at all?

Dan Pashman, host of The Sporkful, has, and his new book, Eat More Better, is filled with deeply researched, science-based hacks to improve your everyday eating. In this episode of Gastropod, Pashman shares his pro tips and dream lunchbox design: listen, learn, and win a copy of his book for yourself.