Discriminating regional characteristics in volatile organic compounds of sun-dried pomfret through HS-SPME-GC×GC-TOFMS

Geographical factors play an important role in the formation of flavor compounds, leading to distinctive regional flavor characteristics of foods. This study investigates the regional aroma characteristics of sun-dried pomfret from South, East, and North China using integrated sensory evaluation, E-nose, and GC×GC-TOFMS. Sensory analysis revealed that samples from North China had higher overall aroma scores, particularly for fatty and fishy aromas. This regional distinctiveness was further confirmed by the E-nose, which segregated the North China samples into a unique cluster. Subsequently, 113 key volatile organic compounds were identified by GC×GC-TOFMS and showed correlations to key sensory attributes, which naturally clustered into three distinct groups corresponding to geographical origins. Among them, 43 compounds were selected as markers by variable importance projection (VIP > 1), predominantly ketones and unsaturated alcohols. Most of them were significantly enriched in North China samples, while styrene was most abundant in South China samples. Further, these markers were validated for regional discrimination through a machine learning model with an accuracy of 90%. This study elucidates the impact of geographical factors on the flavor of dried pomfret and provides scientific evidence for developing its regional characteristics and quality enhancement.