Abstract
Soybean proteins of an acid precipitated protein (APP), a crude 7S globulin (C 7S) and a crude 11S globulin (C 11S) were acetylated at three degrees; low (30%), middle (60%) and high (90%) acetylation. Emulsifying activity of these acetylated proteins decreased in ascending order of the acetyl contents. Emulsifying activity of C 11S remarkably decreased being followed by APP. Highly acetylated C 11S showed nearly no activity. The more the acetyl contents in C 7S, emulsifying capacity and emulsion stability became the higher. These two properties of C 11S increased to the extent of middle acetylation, therafter, decreased. These properties of APP showed also the same tendency as C 11S. High acetylation of C 11S gave remarkable decrease effects on the emulsifying properties.