Determination of Content of Amino Acids in Table Vinegar by Chromatography with Electrochemical Detection

Amino acids in table vinegar were separated and determined by high performance anion-exchange chromatography with pulse amperometric detector.Gradient elution with mixed eluant,containing sodium hydroxide,sodium acetate and water in different proportions,was used to elute the amino acids from the column,and the amino acids were determined with the pulse amperometric detection.Eighteen amino acids were found in 4 samples of table vinegar of different brand and their contents determined by the proposed method.No pre-column or post-column derivatization was necessary.Detection limits for these amino acids were in the range of 1.7-20.0 μg·L-1.Relative standard deviation (n=6) found from the values of retention time for each of these componental amino acids were all less than 1.2%.Values of recovery obtained by standard addition method were in the range of 84%-108%.