What You Need to Know
During fermentation, Aspergillus oryzae secretes proteases and amylases that hydrolyze soybean proteins into amino acids and peptides, and starches into sugars. The resulting glutamic acid and other amino acids impart umami, while volatile compounds develop complex aromas. Salt concentration and temperature control the activity of these enzymes and inhibit unwanted microbes.
The Science
Primary Reaction
Proteolysis and starch hydrolysis by Aspergillus oryzae enzymes during fermentation