EN
In the present study, five Prunus persica L. cultivars, covering all the peach season production in Tunisia, were tested. Flordastar (FS) and Early Maycrest (EMC) which are early cultivars, Rubirich (RUB) which is a cultivar of season and Sweet Cap (SC) and O’Henry (O’H) which are late cultivars. Phenological stages and gas exchange parameters were followed. Fruit quality, sugar and organic acids profile as well as bioactive compounds and antioxidant activities were investigated in exocarp and mesocarp during three ripening stages (1, 2 and 3). The results showed a significant difference in chlorophyll content and assimilation rate among cultivars. In addition, significant difference found in total phenol contents among cultivars and it was ranged in mesocarp between 673.61 and 1966.21 mg 100 g⁻¹ DW in RUB and SC, respectively, during stage 1. During ripening, there was a significant rise in sugar and soluble solids content and a decrease in citric and malic acids in addition to titratable acidity. Phenolic compounds decreased during ripening as well as ABTS and DPPH activities. ABTS activity decreased by 58.35% for FS mesocarp while DPPH activity decreased by 40.81% from stage 1 to stage 3. In conclusion, our results attested that fruit in stage 1 was more abundant in organic acid and phenolic compounds, while fruit in stage 3 was less firm, had best color and concentrated with sugar and total soluble contents. Sweet Cap cultivar exhibited a high phenolic compounds concentration and great antioxidant activity compared to other cultivars.