FERMENTATION OF SOYMILK WITH COMMERCIAL FREEZE-DRIED STARTER LACTIC CULTURES

Fresh soymilk was prepared with 9:1 and 7:1, water:dry soybeans ratio, and fermented with commercial freeze-dried starter cultures comprising three lactics, L. acidophilus. S. thermophilus, and L. bulgaricus. pH and titratable acidity reached their lowest and highest values, respectively, after 8 h of incubation at 43° C. Addition of sucrose did not influence pH or titratable acidity, and utilization of carbohydrate was 0.4%, (expressed as sucrose), irrespective of the initial sucrose level in the soymilk. Taste testing indicated that soy yogurt (4% sucrose, 8 h of incubation), with a final pH of 4.5 and titratable acidity of < 0.5%, expressed as lactic acid, was the most acceptable product. Its storage stability at 5°C exceeded 3 weeks.