Abstract:

To prepare soaking-exempt soybean with better rehydration property, vacuum freeze-drying technology was used to dry fully soaked soybean. Sensory evaluation, CT scanning of internal structure and nutrition determination were also utilized to explore the effects of processing parameters including soaking time, pre-freezing temperature and primary drying temperature on freeze-drying rate and freeze-dried product quality. Results indicated that the optimal processing parameters were soaking time of 18 h, pre-freezing temperature of－90 ℃ and primary drying temperature of －20 ℃, which could provide vacuum freezedried soybean products with high quality. This study can offer a theoretical reference for depth development of soaking-exempt soybean.

Key words: soaking-exempt soybean, vacuum freeze drying, freeze-drying curve