Investigation on Precursor Aromas and Volatile Compounds During the Fermentation of Blackened Pear Vinegar

The acetic acid fermentation stage is a key determinant of fruit vinegar’s aroma profile. Therefore, this study employed GC-MS, HPLC, E-nose and E-tongue techniques, in conjunction with multivariate statistical analysis, to investigate the dynamic changes of compounds during the acetic acid fermentation process of blackened pear vinegar (BPV), as well as the transformation of volatile and non-volatile aroma-active compounds. Results revealed accumulation of organic acids and esters alongside declines in alcohols, aldehydes, and ketones. Isoamyl acetate, benzaldehyde, and nonanal (OAV > 1) were identified as key aroma contributors (VIP > 1, p < 0.05). Total organic acids significantly increased from 4.82 ± 0.53 mg/mL to 10.29 ± 2.38 mg/mL. Correlation analysis revealed a negative relationship between amino acids and volatile compounds, and this negative correlation suggests a possible precursor–product relationship between them. These findings provide theoretical support for the enhancement of fruit vinegar flavor, as well as the application of blackened fruits.