Characteristic aroma changes during the sauce-flavoured black pork processing based on HS-SPME-GC-O-MS and aroma recombination/omission experiments of the final product

To understand the characteristic aroma compounds and their changes during the processing of sauce-flavoured black pork (SBP), headspace solid phase microextraction gas chromatography-olfactometry mass spectrometry (HS-SPME-GC-O-MS) was used to determine the volatiles during processing. A total of 63 volatiles were detected during the whole processing, including aldehydes, alcohols, esters, and furans, etc. The aroma characteristics of SBP are meaty, fatty, fruity, and grassy. During the processing, the aroma characteristics gradually shift from grassy and fruity aromas to being dominated by meaty, supplemented by fruity, fatty, and grassy aromas. Further, the impact of 25 characteristic aroma compounds on aroma changes was visualized through co-occurrence network analysis. Specifically, esters showed increasing centrality (network connectivity) in later stages, indicating their dominant role in transitioning aroma from grassy and fruity to meaty dominance. Ten key characteristic aroma compounds of SBP were confirmed based on molecular sensory science methods: isovaleraldehyde, hexanal, phenylacetaldehyde, eucalyptol, linalool, ethyl butyrate, ethyl 2-methylbutyrate, ethyl isovalerate, ethyl hexanoate, and 2-pentylfuran. Esters are the most important contributor to the characteristic aroma of SBP, with significantly higher content (929.34 μg/kg) and aroma character impact (58 %) than aldehydes (662.35 μg/kg, 25 %).