Experimental study of a novel vacuum sublimation–rehydration thawing for frozen pork

Abstract

• A new vacuum thawing method based on vacuum sublimation and rehydration is proposed. • The thawing principle is verified by experiments under different sublimation times. • The thawing rate is 77% higher than that of natural air thawing. • Mechanisms of vacuum sublimation–rehydration thawing are analyzed and discussed. • Thawed pork can maintain good qualities and its energy consumption is relatively low. For solving the problems of long time and serious nutrient loss in the natural air thawing process, a new vacuum thawing method based on the principle of vacuum sublimation and rehydration thawing (VSRT) was proposed. Frozen pork with an initial temperature of −18 °C and a mass of 3 kg was selected as the research object. The sublimation time as a key parameter of VSRT was set as 10, 20, or 30 min, and the corresponding changes of thawing rate, texture parameters of pork, thawing loss and specific energy consumption were analyzed. The results showed that the overall thawing rate of VSRT was significantly higher than that of the natural air thawing (NAT) method. When the sublimation time was 20 min, the thawing rate was fastest and increased by 77% compared to NAT, the texture parameters of thawed pork were not significantly different from that of raw pork, the thawing loss was relatively less, and the specific energy consumption was lower than that of the microwave thawing method. The mechanism of the thawing process was discussed by illustrating the pressure in the vacuum chamber and core temperature of frozen pork.