High-Throughput Amplicon Sequencing Microbial Communities and Volatile Flavour Compounds of Naturally Air-Dried Yak Jerky from Two Regions of Xizang

Nagqu and Nyingchi, two typical regions in Xizang with distinctly contrasting climatic conditions, are highly representative of the complex and diverse climate patterns across the plateau. This study compared the microbial community structures and volatile compound profiles of naturally air-dried yak jerky produced in these two areas. Significant differences in key physicochemical properties, including pH, moisture content, color, and texture, were also detected between the jerky samples from the two regions. Using high-throughput sequencing and headspace solid phase microextraction-gas chromatograph-mass spectrometry, results revealed significant regional variations in the microbial communities and volatile organic compound (VOC) of yak jerky. For Nagqu City, the dominant bacterial and fungal genera were Gemmiger and Pseudogymnoascus, respectively; whereas in Nyingchi, the dominant bacterial and fungal genera were Brochothrix and Naganishia, respectively. A total of 94 VOCs were identified in the yak jerky, categorized into six classes: 18 aldehydes, 37 esters, 8 alcohols, 3 ketones, 12 hydrocarbons, and 16 others. Esters were identified as the potential contributors to the characteristic aroma profile of yak jerky. These findings provide valuable insights for the standardization and industrial production of yak jerky in Xizang. As this work analysed only four air-dried samples, it should be regarded as a preliminary characterisation; the number of samples needs to be enlarged in further studies.