What You Need to Know
During fermentation, Bacillus subtilis secretes proteases that hydrolyze soybean proteins into peptides and free amino acids, notably glutamic acid, which imparts umami. Concurrently, lipases liberate fatty acids that contribute to depth of flavor, while lactic acid bacteria lower the pH, creating an acidic environment that suppresses spoilage organisms and promotes desirable microbial activity.
The Science
Primary Reaction
Proteolytic hydrolysis of soybean proteins by Bacillus subtilis and lactic acid bacteria, coupled with lipolysis and acidification