Determination of antioxidant vitamins in tomatoes

This study was conducted to investigate the antioxidant vitamin (vitamin E, vitamin C and beta-carotene) content of one of the most important vegetables, tomato, using modern analytical techniques. High-performance liquid chromatographic procedures allowed the separation and quantification of these vitamins as well as their analogues in different cultivars. Carotenoid extract could be fractionated into 14 components, including lycopene, beta-carotene and lutein as the major ones. Paired-ion liquid chromatography provided excellent separation of ascorbic acid with high peak purity. In addition to different analogues of tocopherol, ubiquinone-10 could also be separated and sensitively detected by normal-phase chromatography and fluorescence detection. The highest concentrations (3.15-3.98 mu g g(-1)) of total tocopherol (mainly alpha-analogue) were found in tomato fruits of Katinka, Gitana and Floriset cultivars. The vitamin C content was maximal (36-48 mg per 100 g) in DRW 3126, Primato, Tampo and Monika cultivars. The highest values for beta-carotene were found in Monika, Ultimo and Falcato cultivars (3.5-3.9 mu g g(-1)). The dynamics of fruit ripening were also examined. (C) 1997 Elsevier Science Ltd.