CAROTENOID CHANGES IN THE MESOCARP OF THE REDHAVEN PEACH (PRUNUS-PERSICA) DURING RIPENING

Changes in the carotenoid pattern of the mesocarp of the ''Redhaven'' peach (P. persica) were investigated during the maturation period. In the green fruit, the ratio between the 4 basic chloroplast carotenoids: .beta.-carotene, lutein, violaxanthin and neoxanthin was 1:1:2:1, differing from that found in leaves. The total carotenoid content was low, varying between 5-9 .mu.g/g fresh wt. During ripening the level of .beta.-carotene, lutein and neoxanthin decreased gradually. Levels of violaxanthin followed an uncommon course rising to a maximum as the fruit reached the preclimacteric stage and then gradually decreasing until maturity. The pattern of carotenoids in the climacteric fruit was characterized by the presence of additional pigments such as phytofluene (10%), cryptoxanthin (15%), isolutein (8%) and zeaxanthin (7%). Comparison with carotenoid patterns of 2 other varieties of peach revealed striking differences in carotenoid metabolism during maturation.