Drying characteristics of textured soy protein

Summary Textured soy proteins (TSPs) are commonly used as a functional ingredient in several food applications; its process involves a drying step which is one of the most relevant and challenging processes in the food industry. The drying curves of two commercial types of TSPs were determined in a pilot air‐dryer operated at three different drying air temperatures and velocities, with two different heights of product layer. The results showed that drying air temperature significantly influenced all the experimental curves. The height of the product layer influenced only the drying curves of TSP Type I. The effect of drying air velocity was found to be lower. A two‐constant exponential model and a ten‐constant mathematical model were used in the development of a unified model capable of predicting the drying curves of these types of TSP. The experimental curves were successfully predicted in the range of humidity of industrial interest.