Analysis of flavor profile and mitigation of warmed-over flavor in pre-prepared steamed pork with preserved vegetables using natural spice extracts

This study investigates the formation and mitigation of warmed-over flavor (WOF) in pre-prepared steamed pork with preserved vegetables (PSPPV) using natural spice extracts. Employing headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS), electronic nose analysis, and sensory evaluation, the study explored the changes in flavor and WOF at different key processing points of PSPPV, as well as the impact of spice extracts on the product's quality and WOF. A total of 126 volatile components were detected across the processing stages. Volatile flavor compounds with OAV>10 included eucalyptol, 2-methylbutyraldehyde, n-hexanal, 2-heptanone, and ethyl acetate, while 1-octen-3-ol, n-hexanal, 2-heptanone, and (E)-2-decenal were identified as the primary WOF factors. As processing progressed, the oxidation level of PSPPV increased significantly, with WOF factors mainly forming during the steaming and sterilization processes and reaching the highest levels during sterilization. The addition of rosemary, cinnamon, onion, licorice, and clove extracts, as well as compound spice extracts, significantly reduced the oxidation level of PSPPV and the content of WOF-related compounds such as n-hexanal, n-nonanal, and 2-heptanone. However, these extracts had no significant effect on the content of 1-octen-3-ol, n-octanal, and n-capric aldehyde. Moreover, the natural flavor compounds in the spice extracts enriched the flavor profile of PSPPV. These findings provide valuable insights for the pre-prepared food industry, highlighting the potential of natural spice extracts as effective antioxidants and flavor enhancers. • Analyzed flavor changes using multiple methods; identified 126 volatile components in pre-prepared pork. • Defined volatile flavor differences across processing stages; frying forms key flavor compounds. • Showed oxidation increases during processing; WOF peaks in sterilization. • Found single spice extracts increase oxidation, while compound ones reduce WOF-related compounds. • Confirmed spice extracts optimize flavor, enhance quality, and cut WOF compound formation.