Jon and Greg ask: "What exactly is umami?" (It has nothing to do with anybody's mother.) It's a Japanese word, coined early in the 20th century, meaning "delicious savory taste." Greg explains: "Every time you eat something that's really yummy, like a well-prepared steak, a mushroom risotto, a spaghetti sauce, anchovies, it probably contains umami factors." The Umami Information Center adds:
"Umami is a pleasant savory taste imparted by glutamate, a type of amino acid, and ribonucleotides, including inosinate and guanylate, which occur naturally in many foods including meat, fish, vegetables and dairy products."
Perhaps the best definition of "umami" is the taste itself. Here's a link to Greg Patent's recipe for crab-stuffed portobello mushrooms.
(Broadcast: "The Food Guys," 11/9/14. Listen at 11:20 a.m. Sundays or via podcast.)