Fruit maturation and associated changes in ‘Mosambi’ orange

Fruit maturity changes in terms of physico-chemical, physiological, and sensory characteristics of monsoon-blossom crop of ‘Mosambi’ orange grown under sub-humid tropical climate of central India were studied. Rapid increase in fruit diameter, volume and weight was recorded from 180 to 220 days after fruit set, however, the growth was slow thereafter up to 250 days. Maximum diameter was 8.42 cm, while maximum weight was 253.28 g after 240 and 250 days, respectively. Fruit firmness, peel thickness, peel and rag percentage decreased, while peel colour, TSS/acid ratio and juice content increased from 180 to 250 days. Vitamin ‘C’ content was 56.60 mg/100 ml after 180 days and decreased to 52 mg/100 ml as fruit matured. After 240 days, TSS : acid ratio was 16.63 with 12.82% TSS and 0.78% titratable acids. The p H of the juice increased with fruit maturity. Fruits developed acceptable flavour and appearance after 240 days. ‘L’ and chroma values rose and hue angle (h°) declined with maturation and fruit colour turned yellow after 250 days. Chlorophyll (‘a’, ‘b’ and total) content dropped and total carotenoides in rind flavedo increased significantly. Reducing and total sugars in juice increased. Total phenols in flavedo increased up to 210 days and then declined. Fructose, glucose and sucrose increased in juice with fruit maturity and were in the ratio of 1:2:2 at 240 days. Xylose and maltose were present in trace amounts and ribose was not detected. Respiratory rate declined with fruit maturity confirming non-climacteric nature of ‘Mosambi’ fruit.