Abstract
This study optimized vacuum sublimation-rehydration thawing (VSRT) using an external water vapor generation module (EWVGM) for batch frozen chicken breast processing. The influences of different rehydration temperatures on batch thawing uniformity, thawing effect, thawing efficiency, energy consumption, and rehydration effect were researched. Moderately increasing the rehydration temperature enhanced mass and heat transfer, causing the uniform and quick ice crystal melting. A rehydration temperature of 50 °C was optimal, obtaining the shortest thawing time (80.08 min), the best batch thawing uniformity (with a temperature coefficient of variation of 2.16 × 10-2), the lowest thawing loss (1.15%), the smallest ΔpH (0.01), the lowest ΔE (2.31), the best texture parameters, and the lowest total specific energy consumption (1.465 MJ/kg). Under this thawing condition, with only 158 g of water consumed, the process achieved the highest moisture change ratio (1.85%) and the highest water vapor utilization ratio (23.42%). Compared with air thawing, vacuum steam thawing and VSRT (with internal water vapor generation), VSRT with EWVGM shortened 67.86%, 45.43%, and 14.05% of thawing time, and reduced the temperature coefficient of variation by 78.23%, 72.83%, and 22.02%, respectively. Meanwhile, VSRT with EWVGM obtained the greatest thawing effects, the best energy saving performance, and the highest water vapor utilization ratio. This provided guidance for batch frozen food thawing.