Physicochemical property and metabolic difference of Hongyingzi sorghum from different regions based on multivariate statistical analysis

Using the Hongyingzi sorghum from Renhuai Guizhou, Qianxi Guizhou, and Ezhou Hubei as the research object, the physicochemical indicators were detected by conventional detection methods, and its metabolites were analyzed by using ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) non-target metabolomics technology, the orthogonal partial least squares-discriminant analysis (OPLS-DA) and cluster analysis (CA) were performed based on the results, and the metabolites with significant differences were screened in combination with the variable importance in projection (VIP) value and variance analysis P value (VIP>1, P<0.05). The results showed that there was certain difference in the physicochemical indicators of Hongyingzi sorghum from different regions. The 1 000-grain weight, starch, protein, and tannin contents were 21.24-21.86 g, 65.13%-69.64%, 10.03%-11.01%, and 1.44%-1.60%, respectively. A total of 455 metabolites and 187 significantly different metabolites were identified in the Hongyingzi sorghum from different regions. The results of cluster analysis for the first 25 significantly different metabolites showed that they mainly contained phenolic compounds, organic heterocycles, terpenoids, and amino acids, etc. The contents of phenolic acids, flavonoids and amino acids in Hongyingzi sorghum from different regions related to the Baijiu brewing varied significantly. The contents of phenolic acids, flavonoids and amino acids in Hongyingzi sorghum from Renhuai Guizhou was relatively high, which was more suitable for sauce-flavor (Jiangxiangxing) Baijiu brewing.