Line-Dependent Differences in Volatile Flavor Profiles of Zao-Po Vinegar Wenchang Chicken: An Integrated E-Nose, HS-SPME-GC–MS, and HS-GC–IMS Analysis

Wenchang chicken is a famous indigenous breed from Hainan Province, China, and its characteristic flavor is a key determinant of product quality and consumer acceptance. However, differences in volatile flavor profiles among Wenchang chicken lines under standardized rearing and processing conditions remain insufficiently characterized. In this study, an electronic nose (E-nose), headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC–MS), headspace gas chromatography–ion mobility spectrometry (HS-GC–IMS), biochemical and antioxidant analyses, and Pearson correlation analysis were employed to comprehensively evaluate Zao-Po vinegar Wenchang chicken prepared from twelve Wenchang chicken lines, with three biological replicates per line (n = 3 per line; 36 birds in total). E-nose analysis showed clear separation among different lines, with the first two principal components explaining 97.36% of the total variance. HS-SPME-GC–MS identified 85 volatile organic compounds belonging to 11 chemical classes, of which 14 showed significant line-associated differences after Benjamini–Hochberg false discovery rate (FDR) correction (FDR-adjusted p < 0.05), with decanal, octanal, nonanal, and pentanal among the representative discriminatory VOCs. Pearson correlation analysis, with Benjamini–Hochberg FDR correction for multiple testing, further revealed significant associations between selected biochemical and antioxidant parameters and individual VOCs. These findings suggest potential associations between line-level physiological characteristics and variation in volatile profiles. These results provide a basis for further investigation of the biological mechanisms underlying flavor variation and for the evaluation and utilization of Wenchang chicken germplasm.