紫苏球蛋白乳化性及其O/W乳液的稳定性研究

将紫苏籽粉碎过60目筛后采用石油醚脱脂得到紫苏籽脱脂粉,采用osborne法提取紫苏球蛋白,研究其乳化性质,并将其应用于水包油(oil in water, O/W)乳液,进一步研究紫苏球蛋白浓度对乳液稳定性影响。结果表明,紫苏脱脂粉中球蛋白含量较高,其溶解性、乳化活性和乳化稳定性在pH 2～9,呈现U型曲线;球蛋白质量浓度为2.5～12.5 g/L时,随蛋白质量浓度增大,乳状液粒径、絮凝指数、凝结指数均逐渐减小,界面蛋白含量和质量浓度增加;在14 d贮存过程中,蛋白质量浓度低于7.5 g/L的乳状液均发生脂肪上浮现象,高于10 g/L的乳液贮存稳定性良好。

Emulsifying properties and O/W emulsion stability of Perilla globulin

The perilla seed was crushed, passed through a 60 mesh sieve and degreased with petroleum ether in order to obtain perilla seed degreasing powder. The Perilla globulin was extracted by using the osborne method, and its emulsifying properties were studied. The O/W emulsion of Perilla globulin was applied, In order to study the effect of Perilla globulin concentration on emulsion stability. The results showed that the content of globulin in a defatted powder of Perilla frutescens was high, and its solubility, emulsifying activity and emulsifying stability showed a U-shaped curve in the range of pH 2-9. Within 0.25%-1.25% globulin concentration, with the increase of protein concentration, the particle size, flocculation index and coagulation index of emulsion decreased gradually, and the content and concentration of interfacial protein increased. During the storage of 14 days, the fat in the emulsion with concentration below 0.75% showed floating phenomenon, while the emulsion with a concentration higher than 1.0% showed better storage stability.