AMINO-ACID DETERMINATION IN MUSTS AND WINES BY HPLC AFTER DERIVATIZATION WITH PHENYLISOTHIOCYANATE

The present paper deals with the application of the pre-column derivat ization procedure with PITC to the determination of amino acids levels in must and wine by reverse-phase HPLC. The method can be applied dir ectly to the determination of 19 amino acids in wines, with a relative standard deviation ranging from 1.4% to 3.6% and with an error lower than 5% using the external standard mode. This method can be applied t o the determination of amino acids in musts by external standard proce dure when the sugar content is lower than 50 g/L. Higher concentration of sugar requires the use of an internal standard procedure. Using a- aminobutyric acid as internal standard the results obtained are simila r to those obtained in the determination of amino acids in wines. This procedure has been applied to the determination of 19 amino acids in must and wine of the Chardonnay variety in the Origin Denomination Som ontano (Spain).