More recently, Kim said, Korean politicians have invested heavily in supporting kimchi producers, kimchi science, and kimchi marketing campaigns as a “soft power” strategy to promote the country and its culture overseas. Their efforts have paid off. As Lauryn Chun, the creator of Mother-in-Law’s Kimchi and the author of The Kimchi Cookbook, can attest, today kimchi is found on grocery-store shelves across America, where it’s beloved for its salty, spicy, garlicky crunch, as well as its probiotic potential. Some credit the kimchi taco, which the chef Roy Choi first served from his Los Angeles–based Kogi food truck in 2008, with inspiring kimchi’s cult status among foodies, but kimchi has since gone mainstream: In the past decade, the condiment has begun popping up on chain-restaurant menus from TGI Friday’s to California Pizza Kitchen.

Ta-Nehisi Coates: Ode to the taco truck

Surprisingly, it turns out that all that deliciousness is dependent on a set of microbes—specifically lactic-acid bacteria—that is extremely hard to find on cabbages or in the field. “One thing that I find really fascinating about kimchi compared to other fermented foods is that, unlike cheese or salami or yogurt, where you use starter cultures—these microbes that you buy—kimchi is not inoculated,” says the Tufts University researcher Benjamin Wolfe, who also serves as Gastropod’s in-house microbiologist. This made him wonder: If these bacteria don’t really like to hang out on cabbage leaves, and we don’t intentionally add them to our ferments, where do the microbes that turn cabbage into kimchi come from?

To investigate, we teamed up on an experiment of our own, making multiple large jars of kimchi in an attempt to discover whether the microbes in the final ferment differ depending on the farm where the cabbage was grown. Listen now to find out the results of the experiment—and hear stories of insect-smushing, kimchi block parties, and the kimchi that was specially designed for space!

This post appears courtesy of Gastropod.

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Nicola Twilley is a co-host of the podcast Gastropod and a contributor to The New Yorker. She is at work on two books: one about refrigeration and the other about quarantine.

, and Cynthia Graber is a writer and audio journalist based in Somerville, Massachusettsand a co-host of the podcast Gastropod. H er work has appeared in Scientific American and The New Yorker . Scientific AmericanThe New Yorker