The Science Behind Umami
As far as the cook is concerned, there are two forms of umami, "basic" and "synergizing." Many foods have both, in particular such high-protein foods as meat, milk, mushrooms and seafood.
Basic umami comes from amino acids, particularly glutamic acid, explains food expert David Kasabian, but it must be in the "free" form (the type found in plant or animal tissues) to provide its characteristic taste. In general, the more mature a food, the higher its level of free amino acids — thus the superior flavor of a tomato that has been allowed to fully ripen before harvesting.
Foods composed of "bound" amino acids (those that are part of a protein molecule with other amino acids), on the other hand, need to be coaxed a bit in order to emphasize the taste of umami. This can be accomplished through cooking, in which the heat breaks down the amino acids or through enzymatic action in the form of aging, curing and fermentation. Through these processes, the amino acids become more available for the body to use; the food also increases in umami. And, generally speaking, the more slowly you cook something, the more flavor it develops, including umami.
Foods that are already high in basic umami can get a flavor boost through either cooking or enzymatic action. Dry-aged steak, for instance, has more umami than ground beef; cook that steak and the umami sensation is multiplied. Likewise, sautéed mushrooms have more umami taste than raw mushrooms; as do dried.
Synergizing umami is delivered by nucleotides, chemical compounds that are the building blocks of RNA and DNA. Nucleotides, writes Kasabian, "are found in abundance in meats, shellfish and mushrooms. They too may be in free form or bound up in large, tasteless molecules. Like basic umami, synergizing umami is developed when these large molecules are broken down into their tasty free nucleotides by cooking andenzymatic action. We call this synergizing umami because both research and everyday experience have shown that when synergizing umami is eaten along with basic umami, the umami sensation is multiplied... knowing which foods contain which kind of umami and what state it is in can help you make meals that are
Photos: Courtesy of The Mushroom Council, (top) Oysters Rockefeller, Chef Richard Landeau Horizons, Philadelphia. (bottom) Thai Mushroom Stroganoff, Chef Monica Pope, t'afia, Houston.