Comparative Analysis of Flavour Profile and Aroma Components of Shanxi Aged Vinegar From China

Shanxi aged vinegar (SAV) is a traditional vinegar produced mainly in southern China from rice and wheat, undergoing prolonged fermentation for maturation, which distinguishes it from other vinegar. To explore its flavour, a selection of 12 SAV varieties was meticulously chosen for in-depth aroma analysis. Sensory analysis and electronic nose (E-nose) were used to compare flavour profiles. Volatile components were extracted via liquid–liquid extraction (LLE) with solvent-assisted flavour evaporation (SAFE), analysed by gas chromatography–mass spectrometry (GC–MS) and gas chromatography olfactometry-mass spectrometry (GC-O-MS). The results revealed 145 volatile compounds, predominantly acids, alcohols, ketones and heterocycles, with acids as the most prevalent (ranging from 960.17 to 1231.78 μg/mL). Additionally, 90 aroma-active compounds were identified, notably acetic acid, furfuryl alcohol, 2,3-dimethylpyrazine, lactic acid, phenol, propyl acetate, ethyl propionate and 2(5H)-furanone. Accordingly, a flavour wheel was constructed highlighting dominant volatile components, featuring acidic, alcohol, tangerine peel-like and yeasty aromas. Partial least squares regression (PLSR) analysis showed that the acidity note in SAV positively correlates with acetic acid, isovaleric acid, hexanoic acid, phenethyl alcohol and butyric acid. Understanding the flavour composition of SAV provides vital insight for flavour research and product quality control.