Changes in antioxidant properties and chemical composition during ripening in banana variety 'Hom Thong' (AAA group) and 'Khai' (AA group).
Massive changes in chemical composition and antioxidant properties usually occur in fruits during maturation and ripening. In this study, changes in ascorbic acid content, phenolics content, antioxidant activity (DPPH and FRAP), soluble solid content (TSS) and sugar content during ripening of two banana cultivars at 25 ± 2 o C were investigated. Fully mature green banana fruit (cv. Hom Thong, AAA group and cv. Khai, AA group) were used for the experiment. The total ascorbic acid content of both cultivars was increased slightly with ripening and reduced with the starting of senescence. Total phenolic content in ‘Khai’ banana decreased in the first two days and then significantly increased until day 6. However, the total phenolic content was reduced at the fully ripened stage in both banana cultivars. Total antioxidant activities (DPPH and FRAP) in both cultivars, increased with ripening and decreased rapidly with senescence. ‘Khai’ banana had higher amounts of antioxidant components and total antioxidant activity than ‘Hom Thong’ banana. There was no correlation between antioxidant activities and ascorbic acid content or phenolics content. TSS and total sugar contents increased rapidly in both cultivars until fully ripen stage and then declined thereafter. TSS and sugar contents were highly correlated.