大豆多肽乳液制备及溶剂蒸发法减小粒径研究

Preparation of Soybean Polypeptide Emulsion and Reduction of Particle Size by Solvent Evaporation

大豆多肽是具有营养、呈味和抗氧化等作用的新型多功能天然表面活性剂,小粒径的大豆多肽乳液有助于提高乳液稳定性和乳液成分的消化吸收。将大豆分离蛋白酶解液离心得到可溶性大豆多肽,采用高剪切均质法制备大豆多肽O/W乳液,研究均质速度、均质时间和乳化剂浓度对乳液粒径的影响,结果表明:乳液粒径随三者增大均呈现先减小后略有增大趋势,在均质速度23000 r/min,均质时间4 min和多肽质量浓度10 mg/mL达到最小粒径574 nm。在此基础上,进一步采用乳化-溶剂蒸发法减小大豆多肽乳液粒径,发现乙酸乙酯、环己烷和正己烷3种有机溶剂均有显著效果,其中乙酸乙酯最佳:旋蒸用时最短,乳液稳定性最好,旋蒸后乳液粒径仅323 nm。该研究结果对大豆多肽乳化剂的应用具有参考价值。

Soybean polypeptide,as a novel multifunctional natural surfactant,has functions such as nutrition,taste and anti-oxidation.Small-size soybean polypeptide emulsion is conductive to improving the stability,digestibility,and absorptivity of its components.The soluble soybean polypeptide was obtained by centrifugation of soybean isolate protein hydrolysate.Soybean polypeptide O/W emulsions were prepared by high shear homogenization method.The effects of homogenization speed,homogenization time and emulsifier concentration on emulsion particle size were studied,and the results showed that the particle size decreased first and then increased slightly with the increased values of the three factors,and the minimum particle size reached 574 nm at the homogenization speed of 23000 r/min for 4 min with the polypeptide mass concentration of 10 mg/mL.Emulsification-solvent evaporation method was further used to reduce the particle size of soybean polypeptide emulsion.According to the results,all the three solvents including ethyl acetate,cyclohexane and n-hexane could effectively reduce the particle size.Ethyl acetate was the best among them,with the shortest time of evaporation,the best emulsion stability,and the emulsion particle size of 323 nm after solvent evaporation.This research was valuable for the applications of soybean polypeptide emulsifier.