阿拉伯胶/乳清蛋白乳液的干燥行为特性的研究

Study on Drying Behavior of Gum Arabic/Whey Protein-encapsulated Emulsion

为了研究液滴/颗粒在喷雾干燥过程中的干燥机理,本实验制备以阿拉伯胶和乳清蛋白为壁材的乳液,采用单液滴干燥技术(single droplet drying,SDD)模拟喷雾干燥环境,对单个液滴/颗粒的干燥过程进行分析,探究气流温度和壁材种类对液滴/颗粒干燥行为和所得颗粒性质的影响。结果表明:气流温度为130℃时所得颗粒形态最大,110℃次之,90℃下所得颗粒最小,气流温度高会促进表壳快速形成,进而抑制颗粒收缩,故所得颗粒较大。此外,增大气流温度有利于提高液滴/颗粒的干燥速率。与阿拉伯胶乳液相比,乳清蛋白乳液液滴降速干燥阶段出现早,所得颗粒收缩程度较小。研究结果表明干燥气流温度和壁材种类对表壳形成过程和颗粒形态有显著的影响。

To study the drying mechanism of droplet/particle in spray drying process, the gum arabic/whey protein- encapsulated emulsions were prepared and single droplet drying（SDD） was been proposed that can simulate the environment of spray-drying.The effects of drying air temperatures and types of wall materials on the drying behavior of droplet/particle and the generated particle properties were studied by analyzing the drying process of droplet/particles.The results showed that the generated particle was the largest at drying air temperature of 130℃ ,followed by 110℃, while the generated particle was the smallest at 90℃.At high drying air temperature the earlier formation of crust prevents the particle from shrinking inward.In addition, the increasing of drying air temperature can improve the drying rate of droplets/particles. Compared with gum arabic- encapsulated emulsion,the generated particle of whey protein-encapsulated emulsion drople which deceleration phase arrive earlier has smaller shrink rate. The results indicated that the dry air temperature and the types of wall materials have a significant effect on shell formation behavior and morphology of generated particles.