Abstract:To understand the difference of organic acid content in cooked vinegar in different regions of Sichuan bran vinegar and the change of organic acid content in solid fermentation process，seven main organic acid contents were determined by high performance liquid chromatography.The results showed that in the solid state fermentation process of Sichuan bran vinegar，acetic acid increased from 1.271 2 mg/mL to 3.121 4 mg/mL，which was the highest content acid，accounting for 58.12%of total organic acid.The content of lactic acid was increased from 0.885 8 mg/mL to 1.321 6 mg/mL，accounting for 32.67%of the total organic acids.The changes of acetic acid and lactic acid were the most significant，and the changes of oxalic acid，citric acid，tartaric acid，citric acid and tartaric acid were not obvious.Principal component analysis of the results showed that in cooked vinegar，lactic acid showed a high correlation with Sichuan bran vinegar.The content of lactic acid in Sichuan bran vinegar was significantly higher than that in other regions，indicated that lactic acid can effectively distinguish Sichuan bran vinegar from its regional vinegar.In the solid-state fermentation process of Sichuan bran vinegar，3 to 10 days before fermentation showed a high correlation with lactic acid，and 12 to 23 days lat－er had a high correlation with acetic acid.