Reduction of Levels of Volatile Components Associated with the "Beany" Flavor in Soymilk by Lactobacilli and Streptococci

ABSTRACT: Methanol, acetaldehyde, ethanol, and hexanal were the 4 major volatiles detected in unfermented soymilk. Eight of the cultures of lactobacilli or streptococci completely eliminated hexanal in the soymilk during fermentation. However, there were considerable variations in the effects of the cultures on the other 3 compounds. All 8 caused significant reduction in levels of methanol. Streptococcus thermophilus OSU-2 was the only culture that significantly lowered the concentration of ethanol in the soymilk. All except Lactobacillus acidophilus C19 and Lactobacillus casei E5 significantly lowered the level of acetaldehyde. Of the cultures tested, L. acidophilus L1 offered the best potential for producing fermented soymilk with an improved volatile profile.