New insights from flavoromics on different heating methods of traditional fermented shrimp paste: The volatile components and metabolic pathways

Traditional Chinese fermented shrimp paste is popular with consumers for its unique seafood flavor and fermented aroma. However, different heating methods exerted various flavors, which directly affect consumer choice and the industrialization of shrimp paste. In this study, the effect of four heating methods (steaming, frying, microwaving, and infrared) on volatile components of shrimp paste were compared by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC–MS), gas chromatography–ion mobility spectrometry (GC-IMS) and chemometrics. Results showed that 96 volatile components were identified; The volatile components such as pentanal, ethyl acetate, dimethyl disulfide, and propanal were the characteristic volatile components that could be distinguished between different heating methods. The concentration of phenols and alcohols decreased, and the concentration of ketones and aldehydes increased after heating. The effect of microwave heating on volatile components is closer to that of steaming and frying, while infrared heating had the most significant impact on volatile components of shrimp paste. In addition, steaming, frying, microwaving, and infrared heating improve the aroma quality of shrimp paste by promoting fat oxidation, protein degradation, the Strecker pathway, and the escape of sulfur-containing compounds. Therefore, our results can provide theoretical support for improving shrimp paste quality and consumer choice.