冷榨芝麻油微胶囊乳状液乳化条件及乳化体系研究

EMULSIFYING CONDITIONS OF THE MICROENCAPSULATION EMULSION OF COLD-PRESSED SESAME OIL

研究了制备冷榨芝麻油微胶囊的乳状液乳化工艺条件及乳状液的黏度、粒径.根据乳状液的稳定性选择大豆分离蛋白和β-环糊精复合作为包埋壁材,选用蔗糖酯S-15、单甘酯作为乳化剂制备冷榨芝麻油微胶囊乳状液,得出最佳的乳化条件为：乳化温度70℃,剪切时间4 min,乳化剂复配比例为2∶1,此条件下制备的冷榨芝麻油微胶囊乳状液稳定指数均值可达98.2%.采用TA-DHR-1型流变仪研究冷榨芝麻油微胶囊乳状液的黏度表明：乳状液黏度在初始阶段发生剪切变稀,随着剪切速率不断增加,其黏度也趋向稳定.乳状液总固形物含量为17%-22%时乳化效果较好.冷榨芝麻油微胶囊乳状液的粒径测定结果表明：乳状液粒径大多分布在1-10μm的区间内,占81.93%,说明乳状液粒径大小分布较为集中、均匀.

Cold pressed sesame oil contains abundant nutrients,but its antioxidant ability is weak. Microencapsulation can increase the oxidation stability of the sesame oil. The present study was to investigate the emulsifying conditions for preparing microencapsulated cold-pressed sesame oil emulsion, and the viscosity and particle size of the emulsion. The isolated soybean protein and/3-cyclodextrin were chosen as wall materials according to the stability of microcapsule emulsion,while sucrose ester S-15 ,monoglyceride and casein acid sodium were chosen as emulsifiers. The optimum conditions of emulsion was obtained through the orthogonal experiment and the change of emulsion viscosity was determined using TA-DHR-1 rheometer. The results showed that the optimized condition was as follows： emulsification temperature of 70℃ ,shearing time of 4rain, emulsifier complex ratio of 2：1 （sucrose ester to monoglyceride）, while the stability of emulsion was up to 98.2%. The TA-DHR-1 results showed that the emulsion had a thin viscosity at the beginning of process,and the viscosity tended to stable following the shear rate increasing. The emulsifying effect was best while the total solids content of the emulsion was 20%. The measurement of emulsion particle diameter showed that the emulsion particle size was uniform, and mostly distributed in the range of 1 - 10 μm, accounting for 81.93% of the total particles.