Twenty-two citrus cultivars belonging to three citrus species, namely, orange (Citrus sinensis (l.) Osbeck) (eleven cultivars), mandarin (Citrus reticulata L.) (four cultivars) and lemon (Citrus limon L.) (seven cultivars) were assessed for fruit quality characteristics and juice phytochemicals at maturation. Titratable acidity, pH, total soluble solids, beta-carotene, total phenolic compounds, total o-diphenols, total flavonoids, and antioxidant capacity based on DPPH and FRAP assays were assayed. Lemon varieties were characterized by the lowest juice pH and by high titratable acidity. Total soluble solids were high in mandarins, followed by oranges and lastly by lemons. Carotenoids were determined in highest concentration in mandarin varieties while the lowest concentration was found in lemons. Oranges were characterized by high concentration of total phenols, with 'Salustiana' exhibiting the highest value. Valencia clones exhibited the highest concentrations of both o-diphenols and flavonoids. On the other hand Clementine mandarins and lemons were characterized by high antioxidant capacity, higher than that observed in most of the orange varieties assayed and of 'Encore' and 'Kara' mandarins. The principal component analysis (PCA) revealed an interesting classification of the varieties assayed. Lemon varieties were grouped together; 'Kara' and 'Encore' mandarins belonged to the same group while Clementine mandarines were grouped with orange varieties. Based on the present results it is clear that most of the varieties assayed in this experiment presented typical juice quality characteristics of the species they belong to, so that they could be easily distinguished in groups, except those of Clementine mandarins which presented similar quality characteristics with the orange varieties.
