Effect of Ultrasonic Assisted Salting on Quality of Microwave Snakehead Fillet

In order to study the effect of ultrasound-assisted salting on the flavor quality of microwave heating snakehead fillet, the parameters of ultrasonic and brining of snakehead fillet were first investigated, then the electronic nose, electronic tongue, volatile substances and free amino acid substance of microwave heated snakehead fillets were determined. The results showed that the optimum parameters of ultrasound-assisted brining were as follows: Salt content 4 g/mL, solid-to-liquid ratio 1:4 g/mL, constant temperature (24±1) ℃, ultrasonic frequency 40 kHz, ultrasonic power 200 W and ultrasonic time 60 min. In electronic nose and volatile flavor substances analysis, ultrasonic assisted salting treatment effectively inhibited the formation of organic sulfide and increased the contents of five volatile substances (alcohols, aldehydes, ketones, acids and esters) in microwave heated fillets. In electronic tongue and free amino acid substance content analysis, the response of ultrasonic assisted salting treatment to sour and bitter taste was the lowest, and the response to salty, umami and sweet taste was the highest. And the ultrasonic treatment increased the contents of 13 free amino acids of microwave heated snakehead fillet, suggesting the improvement of flavor and taste. Two-factor analysis of variance found that ultrasonic treatment had a more significant effect on flavor, and salting treatment had a more significant effect on taste. The results of this study provide theoretical support for the industrial production of prefabricated aquatic products.