Abstract:

To investigate the effect of different soybean pretreatment methods on the quality of soy milk, five pretreatment methods
were chosen, and the sensory quality, color, stability, and the contents of major nutritional components and anti-nutritional factors
in soy milk made from the treated soybeans were analyzed and compared. The results showed that different soybean pretreatment
methods had different effects on the quality of soy milk. The preparation of soy milk from dry soybeans was convenient, but its
quality was not so good as that prepared from soaked soybeans, due to the inferior sensory quality, poorer stability, and lower
contents of proteins and polysaccharides, as well as higher contents of anti-nutritional factors. The sensory quality, stability and
removal efficiency of anti-nutritional factors of soy milk made from soybeans cooked at high temperature and high pressure, with
darker color and a severer protein loss, were worse than those of the soy milk prepared from soaked soybeans Similarly, the protein
content in soy milk prepared from the cooked soybeans was lower than that prepared from dry soybeans. Compared with soy milk
prepared from dry soybeans, the quality and stability of soy milk prepared from soaked soybeans were efficiently improved, the
contents of protein, soluble solids and polysaccharide were significantly increased, and the contents of anti-nutritional factors were
significantly decreased (P < 0.05). Moreover, the overall quality of soy milks prepared from soaking-free soybeans and NaHCO3
solution-soaked soybeans was the best, with the brightest color.

Key words: pretreatment, soy milk, main nutritional component, anti-nutritional factor