Tracking the volatile fingerprint of crayfish by-product shrimp sauce during a rapid fermentation: A synergistic strategy using flavoromics and molecular docking.

Crayfish heads were rapidly converted into shrimp sauce via enzymatic pretreatment and fermentation within 30 days. The evolution of volatile organic compounds (VOCs) during shrimp sauce fermentation was analyzed. Electronic nose analysis showed the flavors changed over time, with distinct VOCs between the fermented product and the enzymolysis solution. GC-MS identified 174 VOCs, including aldehydes, aromatics, and alcohols like 1-octen-3-ol, furfural, etc. Gas chromatography-ion mobility spectrometry (GC-IMS) detected 63 VOCs, indicating obvious differences during fermentation. 1-Octen-3-ol, octanal, and guaiacol were identified as key flavors using the odor activity values. Correlation analysis revealed that (E)-2-octenal was negatively correlated with fatty acid content. Octanal and nonanal were negatively correlated with free amino acid content. Molecular docking showed OR1D2 and OR1A1 had strong binding affinity to phenolic and aromatic aldehydes. The results indicate that key VOCs in fermented shrimp sauce are closely related to the degradation of fatty acids and free amino acids.