Study on Microwave Sterilization Process and Quality Evaluation of Instant Crayfish (Procambarus clarkii)

In order to develop the industrial process of high-quality instant crayfish (Procambarus clarkii) products, the microwave sterilization processes were designed based on the 896 MHz single-mode microwave sterilization system. Effects of microwave sterilization on crayfish quality were studied by calculating cooking value, water holding capacity, texture analysis, color analysis, sensory evaluation and taste profile analysis of electronic tongue. Study results indicated the sterilization conditions of keeping the microwave in power of 6.5 kW and pressure of 0.2 MPa, microwave treating for 190 s, holding at （120±1）℃ for 180 s could achieve the level of thermal lethality of F₀=2 min, which was the minimum thermal lethality value satisfying the requirements of commercial sterility. The shelf life of the instant crayfish treated by the microwave sterilization process could be more than 6 months at room temperature. The total processing time, cooking value of cold spot and surface in microwave sterilization group were significantly reduced by 66.55%, 34.40%, and 57.75% than those of traditional sterilization treatments, respectively. Moreover, the water holding capacity and texture of crayfish in experimental microwave sterilization group were much higher compared to the traditional sterilization treated group (P<0.05), and there was no significant difference of ratio of intact tail were found in both groups (P>0.05). However, the color of muscle of crayfish treated with microwave sterilization turned yellower than that of traditional sterilization group. During the storage period, the taste profile of microwave sterilization group did not change significantly, and the sensory score of microwave sterilization group was higher than that of traditional sterilization group. In conclusion, microwave sterilization technology can be used in the processing of room-temperature instant crayfish products.