The changes of flavor substances of sweet and sour crispy fish during the deep-frying process

Abstract

Objective: This study aimed to provide the theoretical foundation for the industrialization production of sweet and sour crispy fish. Methods: The changes of aroma and taste compounds were assessed by using the electronic-nose, electronic-tongue, GC-IMS, and automatic amino acid analyzer, along with the principal component analysis, clustering analysis and correlational analysis. Results: The results showed that the aroma response intensity increased and then decreased, and the taste response intensity increased during the deep-frying process. According to the GC-IMS analysis, a total of 46 aroma compounds were detected, including 7 aldehydes, 5 ketones, 10 alcohols, 9 esters, 4 olefins, 7 heterocyclic compounds and 4 other components. The relative content of alcohols in A sample (fried-forming for 1.5 min) was maximum, and the relative content of aldehydes and ketones in the B sample (fried-forming for 3.0 min) was maximum. A total of 21 free amino acids were identified. Among them, glutamic acid, alanine, and arginase made a greater contribution to the umami, sweet and bitter taste respectively. The umami taste in C samples (cooking for 1.0 min) was outstanding. The correlational analysis results showed that alcohol compounds presented a significant positive correlation with most of the sensors of electronic-nose (P＜0.05). Delicate amino acids and the sensors of AHS, PKS, CTS and NMS exited a markedly positive relationship (P＜0.05). There was a significantly negative correlation between aldehydes and sweet and bitter amino acids (P＜0.05). Conclusion: Most aroma compounds of sweet and sour crispy fish increased first and then decreased, and the taste compounds increased during the deep-frying process.

Keywords

• sweet and sour crispy fish
• deep-frying
• flavor substances
• aroma component
• free amino acids