微射流处理对发酵豆乳流变学特性及微观结构的影响

Effect of Microfluidization Treatment on Rheological Characteristics and Microstructure of Soy Yogurt

摘要:

以添加2%浓缩乳清蛋白的豆乳为原料，经过不同压力的微射流处理后，利用瑞士乳杆菌(Lactobacillus helveticus LH-B02)和干酪乳杆菌(Lactobacillus casei L.casei-01)组合发酵制备发酵豆乳，研究了微射流处理对发酵豆乳流变特性和微观结构的影响。结果表明，豆乳经过微射流处理后，制备的发酵豆乳持水力增大，同时表现出较强的粘弹性以及剪切稀化特性，表观粘度和屈服应力也有所增加，并且随处理压力的增加，这种趋势愈发明显。此外，微射流处理后，发酵豆乳的微观结构中孔隙变小，蛋白之间交联增多，整体呈现出更加均一致密的凝胶网络结构。

Abstract:

Rheological characteristics and microstructure of probiotic soy yogurt were studied in this research. Lactobacillus helveticus LH-B02 and Lactobacillus casei L.casei-01 were used to ferment soymilk microfluidized at different pressures. Results indicated that: microfluidization of soymilk led to a prominently higher water holding capacity (WHC) of soy yogurt. Meanwhile, soy yogurt elaborated from microfluidized soymilk showed stronger viscoelastic and shear-thinning properties, higher apparent viscosity and yield stress. Moreover, smaller but more pores, more interconnections among protein aggregates were observed in microstructure of soy yogurt prepared from microfluidized soymilk, exhibiting a more homogeneous and compact gel network.