Influence of Ethanolic Soaking of Soybeans on Flavor and Lipoxygenase Activity of Soymilk

Soymilks were prepared from soybeans soaked in 15% ethanol and in 15% ethanol plus 0.1M NaOH, 0.1M Na 2 CO 3 or 0.1M NaHCO 3 for various times at 60°C. The ethanol was removed before processing the soybeans into soymilks, and the soymilks were analyzed for composition, lipoxygenase activity, TBA number, and flavor (paintiness, grassiness, nuttiness, cereal, and astringency). The change in paintiness with time of soaking did not depend only on lipoxygenase activity or on TBA number, but was related to the soaking conditions. Soaking in 0.1M NaOH gave soymilks with more paintiness than soaking in either 0.1M Na 2 CO 3 or NaHCO 3 .