Determination of the Free Amino Acid, Organic Acid, and Nucleotide in Commercial Vinegars.

The selected taste-active compounds in several kinds of commercial vinegar including amino acids, organic acids, and nucleotides were determined by High Performance Liquid Chromatography (HPLC). The results showed that glutamine and alanine, which contribute the umami and sweet taste to the flavor of vinegar, are high in Taste Activity Value (TAV). Acetic acid is the major organic acid in vinegar, making up as much as 91.4% of the total organic acid composition. Nucleotides, which were only detected in 5 brands of commercial vinegar and are both low in TAV, contribute less taste in vinegar. Our research provides a multiple chemical compositional characterization of vinegar and proposes a possibility of classification of different kinds of vinegar.