On Food and Cooking

Japanese Soy Sauce Most of the soy sauce
sold in the West is made in Japan or in the
Japanese style, which is summarized in the
box on p. 498. During the initial brief
fermentation, the Aspergillus mold produces
enzymes that will break down wheat starch
into sugars, wheat and soy proteins into amino
acids, and seed oils into fatty acids. Then
during the longer main fermentation, these
enzymes do their work; yeasts produce
alcohol and a range of taste and aroma
compounds; and bacteria produce lactic,
acetic, and other acids, and yet other aromas.
Over time, the various enzymes and microbial
products also react with each other, the sugars
and amino acids forming roasty-smelling
pyrazines, acids and alcohols combining to
form fruity esters. The high-temperature
pasteurization develops yet another layer of
flavor by encouraging browning reactions
between amino acids and sugars. The result is
a liquid that’s salty, tart, sweet, savory (from