大豆分离蛋白包埋特性的研究

Research of Encapsulation Properties of Soy Protein Isolate

本实验通过大豆分离蛋白作为包埋壁材制备不同均质压力(40、80 MPa)、入口温度(160～200℃)、芯壁比(1/2～3/1,m/m)和固形物含量(10～20%)的原始乳液进行喷雾干燥得到粉末样品,将部分储藏于25℃相对湿度75%的干燥器中待吸湿平衡后得到对应湿粉。测定原始乳液及干、湿粉末复溶乳液的粒径大小分布,干、湿粉末的水分含量、包埋效率和溶解速率,并用扫描电镜观察样品的微观形态。结果表明,芯壁比对喷雾干燥所得粉末的溶解性质、包埋性质、潮湿环境储藏稳定性及表面形态均有显著影响,此外均质压力、入口温度及固形物含量也不同程度地影响干、湿粉末的包埋特性。

Emulsions of soy protein isolate （SPI） solutions and soya oil at cow/wall ratios of 0.5-3.0 （m/m） with solid content of 10-20% were prepared by homogenization at 40MPa and 80MPa. The resulting emulsions were subsequently spray-dried at 160-200 ℃ inlet temperatures to produce microcapsule powders. Part of them were stored in relative humidity 75 % atmosphere at 25℃and obtained samples when moisture sorption equilibrated. The droplet size dislribution of fresh and reconstituted emulsions were determined, also moisture content, extractable oil, encapsulation efficiency （ME） and dissolution rate of powder samples were characterized, the morphology of powders with different core/wall ratios were established by SEM. The results indicated core/wall ratio had markedly influence on many properties of mierocapsule powders. Furthermore, homogenization pressure, inlet temperature and solid content affected encapsulation properties of powder samples in different extent.