What You Need to Know
During fermentation, Bacillus subtilis secretes proteases that hydrolyze soy proteins into peptides and amino acids, while also producing extracellular polysaccharides that give the product its characteristic viscosity. The same enzymes generate nattokinase, a serine protease with antithrombotic activity, and the breakdown of proteins releases ammonia and volatile amines that contribute to the pungent aroma.
The Science
Primary Reaction
Thermophilic fermentation of soy proteins by Bacillus subtilis natto