Effect of different thermal processing methods on flavor characteristics of Penaeus vannamei

This study explored the effect of three thermal processing methods, namely drying, steaming and microwaving on non-volatile and volatile flavor compounds of Penaeus vannamei; electronic tongue, electronic nose and gas chromatography-ion mobility spectrometry (GC-IMS) were used in combination with multiple statistical methods. Correlation analysis of the results showed that these processing methods resulted differences in flavor composition; the non-volatile flavor compounds, such as sweet free amino acids, 5′-nucleotides, and organic acids were higher in thermal processed samples. Aspartic acid, glutamic acid, succinic acid, guanine nucleotide, and hypoxanthine nucleotide were main flavor active components. Additionally, the volatile flavor compounds determined were 38 compounds via GC-IMS analysis, which mainly included 9 alcohols, 8 esters, 6 aldehydes, 4 ketones, 4 acids, 1 ether, 1 pyrazine, 1 furan, 1 thiazole, and 3 others. Based on these flavor profiles, the principal component analysis of E-tongue and E-nose data showed a distinct difference among the different thermally processed samples. Overall, the diversity and content of flavor compounds were higher in dried and microwaved samples than in steamed ones, indicating the former two processing as better methods. This study is expected to provide knowledge for consumers to choose thermal processing method while purchasing Penaeus vannamei products.