Analysis of the basic components and free amino acid composition of pineapple fruit vinegar

Acetic acid fermentation is an essential step in producing high-quality vinegar. In this study, the alcoholic medium was used as a seed broth for acetic fermentation using Acetobacter aceti as the inoculum for approximately 7 days at 32℃ to obtain 45.87g/L acetic acid. During the Acetic acid fermentation stage, the content of the total polyphenols decreased first and then increased. Based on amino acid analyzer analysis, pineapple vinegar contains 18 kinds of free amino acids. And the contents of sweet and umami free amino acids are the main free amino acids, followed by bitter amino acids