This study was undertaken to find out the effect of phytate on the protein digestibility of various soybean foods, including soy milk, bean curd, curd residue, cheongkukjang, soy sauce, and soy paste. The phytate content of soybean was 2.4%, which decreased to 0.2%, 0.7%, and 0.4% in soy milk, bean curd, and curd residue, respectively, and to 0.2% and 1.0% in soy sauce and soy paste, respectively. The phytate/protein ratio was not correlated with protein digestibility by pepsin whereas the ratio was highly correlated with pancreatin digestibility (p$lt;0.01, r= -0.73). According to SDS-PAGE for the soluble protein fractions, soaked bean showed an alteration in soluble components and bean curd residue exihibited newer low molecular weight bands. Fermented soy products showed no protein band, likely due to degradation.
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