Organic acid compositions of 11 different white grape cultivars and grape juices were determined by high-pressure liquid chromatography (HPLC). The ranges of acid concentrations found in grapes were as follows: citric, 30-164 mg/l; tartaric, 4.98-7.48 g/l and malic, 1.43-3.40 g/l. Also the ranges of acid concentrations found in grape juices were as follows: citric, 31-181 mg/l, tartaric, 4.07-4.92 g/l and malic, 1.36-3.47 g/l. Tartaric acid was the major acid in every grape variety analyzed. Grape juices had a lower tartaric acid content than grapes due to detartration process. (C) 2003 Elsevier Ltd. All rights reserved.