Rheology and microstructure of yogurt

Yogurt is a popular fermented dairy product with a special structure. The milk undergoes a series of biochemical changes with the addition of starter cultures and transforms the milk into several intermediary products that finally achieve the desired three-dimensional consistency/texture. Rheology plays an important role to understand the gelation, micro-structure, and flow behavior of yogurt. There are many factors that influence the rheology, microstructure, and textural properties of yogurt including the source of milk, selection of starter culture, production process, packaging, and storage. Rheological measurements of stirred yogurt have been conducted using steady flow, small amplitude oscillatory shear, and large amplitude oscillatory shear. To address all the structural information of yogurt, the chapter deals with the understanding of the rheology and microstructure of yogurt using various measurement systems and their importance to the industry and consumers.