Food, Meet Fungus


Your host Christina in a
tempeh kitchen, for science!

In her episodes of Transistor, biologist Christina Agapakis is exploring the microbiome: the trillions of bacteria, fungi, and viruses that live in and on our body. The microbiome is hot right now and in these episodes Christina will explore what we do know in the face of so much hope and hype.

She starts with food. Bacteria-rich foods such as tempeh, cheese, pickles and yogurt have long been praised for their probiotic effect. But can you really add enough good bacteria to your digestive system to outnumber the bad?

Inside the Episode:


Barry’s business partner Gordon Bennett
mixing the Rhizopus culture into the soybeans.

Christina pays a visit to an industrial kitchen in Long Island City, Queens, where Barry Schwartz and a small team meet up every other week to make Barry’s Tempeh, the only fresh tempeh sold in New York State.

Wanting to better understand tempeh – aka “blue cheese of tofu” – Christina then calls her friend Colin Cahill in Indonesia where tempeh originated. He explains how it’s more than just soybeans and fungus that give tempeh in Indonesia its regional flavor.

Then, if a single bacteria food like tempeh is good, studying a more complex ecosystem like the bacteria on cheese rind might tell us more about bacteria interact with each other and in our digestive systems – at least that’s Harvard biologist Rachel Dutton‘s goal. She’s studied more than a hundred different types of cheese from around the world, trying to better understand how cheese gets its flavor and why they are all so different. She’s now the go-to biologist for world-famous chefs like David Chang of Momufuko and Jim Lahey of Sullivan Street Bakery in New York, helping them explore ways to make foods taste new, different and better.

Christina then shares her early love of fermentation with fermentation revivalist Sandor Katz. Sandor’s never met a fermented food he didn’t like, but he’s skeptical of anyone who says fermented foods can make us healthy on their own.

This episode was produced by Kerry Donahue and Sruthi Pinnamaneni, and mixed by Tim Einenkel.

We Are Stardust


We’re closer than ever before to discovering if we’re not alone in the universe. The host for this episode of Transistor, astrophysicist Michelle Thaller, visits the NASA lab that discovered that meteorites contain some of the very same chemical elements that we contain. Then, Michelle talks to a Vatican planetary scientist about how science and religion can meet on the topic of life beyond Earth.

Inside the Episode:

Astrobiologist Danny Glavin works at the NASA Goddard Center for Astrobiology. Here are some of those “mad scientist machines” from the lab.


This nanoelectrospray emitter is used by the lab to analyze very small samples. It gives sample molecules an electric charge, then transfers them to a mass spectrometer, which identifies the molecules by their mass.


Mass spectrometer instrument used to detect amino acids in meteorite sample extracts.

Learn more about Vatican planetary scientist Br. Guy Consolmagno and his most recent book.

This episode was produced by Lauren Ober and edited by Katie Davis. Mix and sound design by Whitney Jones.

Photos courtesy of NASA.

Meet Transistor

Hello science lovers and people who dig a good story:

Transistor is a new weekly podcast of scientific questions and curiosities, with many episodes hosted by key scientists at the forefront of discovery.

Head here for more details, but we know you just want to dig right in and start listening. Our first four episodes are:

  • We Are Stardust: Astrophysicist Michelle Thaller visits the NASA lab that discovered that meteorites contain some of the very same chemical elements that we contain. She also talks to a Vatican planetary scientist about how science and religion can meet on the topic of life beyond Earth.

  • Food, Meet Fungus: The microbiome — the trillions of bacteria, fungi, and viruses that live in and on our body — is hot right now. Biologist Christina Agapakis explores what we do know in the face of so much hope and hype, starting with food.
  • Totally Cerebral: Untangling the Mystery of Memory: Neuroscientist Wendy Suzuki introduces us to scientists who have uncovered some of the deepest secrets about our brains. She begins by talking with experimental psychologist Brenda Milner, who in the 1950s, completely changed our understanding of the parts of the brain important for forming new long-term memories.
  • Totally Cerebral: The Man Without a Memory: Imagine never being able to form a new long term memory after the age of 27. Welcome to the life of the famous amnesic patient “HM”. Wendy Suzuki talks with neuroscientist Suzanne Corkin, who studied HM for almost half a century and gives us a glimpse of what daily life was like for him, and his tremendous contribution to our understanding of how our memories work.

Subscribe so you don’t miss an episode of Transistor, and follow us at @TransistorShow.

PRX presents Transistor, applying our storytelling and podcast experience to science. Transistor is supported by the Alfred P. Sloan foundation, enhancing public understanding of science, technology, and economic performance. Learn more at sloan.org.