THE UMAMI EXPERIENCE

What is it?  It's a taste that we've all experienced but have not necessarily put into words.  The Japanese define umami as "deliciousness" and define it as the "fifth taste" distinct from sweet, salty, bitter and sour.  Other descriptions of the fifth taste in foods are "robust" and "meaty".   This may be a taste differential that is difficult for some to define as it is a subtle taste that blends in well with other tastes.

Umami is both a basic taste and a flavor enhancer produced by the presence of a specific chemical compound - free glutamate.  First isolated in Japan in 1908, glutamate is a form of glutamic acid, one of the most abundant amino acids in food. Glutamate is to umami what sodium chloride (table salt) is to saltiness. Recently, scientists have discovered tongue receptors that seem to react only to glutamates, which supports the case for making umami the fifth taste.

Mushrooms are high on the umami scale as they contain abundant amounts of glutamates. The resulting "meaty" flavor offered by mushrooms, along with their distinctive texture, explains why they so successfully stand in for meat in vegetarian dishes. Other glutamate-rich foods include tomatoes, Parmesan cheese, soy sauce, bonito flakes and kelp.

The story of umami doesn't end with glutamate. A group of compounds called ribonucleotides have been found to work synergistically with glutamate to heighten the "umami-ness" of foods.  We all know that mushrooms are perfect partners for many kinds of meat, poultry and fish; it's because the free glutamate in mushrooms complements certain ribonucleotides naturally occurring in protein foods. Scientists hypothesize that the ribonucleotides prime the glutamate receptor sites on the tongue to provide a more intense umami taste sensation.

Here are two recipes that will help you to experience the umami sensation for yourself:

SAVORY STIR-FRIED MUSHROOMS

Adapted from Jack Czarnecki's "Joe's Book of Mushroom Cookery" (Atheneum,1988)

Heat a large skillet or wok over medium high heat; add peanut oil. Stir-fry green onions 30 seconds, then add mushrooms. Continue to stir-fry until liquid begins to evaporate and mushrooms begin to brown, about 6 minutes. Stir in soy sauce, salt and sugar. Serve over rice or pasta, or with grilled meats.  Yield: about 4 portions

MISO SOUP WITH MIXED MUSHROOMS

Adapted from The Japanese Kitchen by Hiroko Shimbo (The Harvard Common Press, 2000)

Cut mushrooms into thick strips. In a 3-quart saucepan, heat oil over medium-high heat. Add onion; cook until tender, about 3 minutes. Add mushrooms and green onions; cook and stir for 20 seconds. Add dashi; bring to a boil. Stir in miso until dissolved. Serve immediately; sprinkle with Shichimi togarshi (seven-spice powder), if desired. Yield: 4 portions *Japanese broth made from dried tuna flakes (bonito) and seaweed.  Can be quickly made from granules or a concentrate found in Asian specialty food stores.