Discrimination of Tibetan Pork by Geographical Location using the Volatile Organic Compound (VOC) Composition by Headspace Solid-Phase Microextraction Gas Chromatography–Mass Spectrometry (HS-SPME-GC–MS)

Abstract

The geographical environment and climate may affect the quality and volatile organic compounds (VOCs) of Tibetan pork. In this study, the physicochemical indices and VOCs of Tibetan pork from Beichuan, Sichuan (BS); Meishan, Sichuan (MS); Aba, Sichuan (AS); Tongchuan, Shaanxi (TS); and Diqing, Yunnan (DY) China were determined by headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS) with chemometrics methods. A discriminant model was established to screen the potential volatile markers of pork from different geographical locations. Tibetan pork maintains the advantages of high protein and low fat after being introduced to low-altitude areas. A total of 40 VOCs were identified from Tibetan pork, including aldehydes, esters, alcohols, hydrocarbons, acids, ketones, and sulfur heterocyclics. Tibetan pork from the locations was distinguished by principal component analysis (PCA). Moreover, nine volatile markers, including hexanal, benzaldehyde, 2-pentyl-furan, heptanal, 3-ethylcyclohexene, octanal, nonanal, formic acid, heptyl ester, and styrene, were employed to identify the origin of Tibetan pork based on partial least squares discriminant analysis (PLS–DA) combined with cluster analysis. The developed method distinguished the VOCs of Tibetan pork by geographical location. This study provides a reference for the objective evaluation of the origin of Tibetan pork.