The Effect of soybean pre-treatment on the quality of soymilk

Abstract

Three factors, namely hulling, cooking time, and the fermentation time were investigated for their effect on the quality of soymilk. Analysis of variance showed no significant differences between hulled and unhulled treatment on the water soluble protein, pH of soymilk after processing, and general acceptability of soymilk formulated with 20 ppm vanilla. However, total protein content, amino acid nitrogen, viscosity, pH of soymilk before processing, and general acceptability of soymilk formulated with 20% fresh milk are significantly affected. Treatment of unhulled soybean shows higher values than hulled soybean. There is relationship between cooking time and total nitrogen content, water soluble protein, and viscosity. Regression analyses showed that the total protein content, water soluble protein and viscosity decreased and reached the minimum value when soybean was cooked between 10 to 20 minutes, but increased again as heating continued to 30 minutes....