Post-Harvest Ripening Changes in Wood Apple (Feronia elephantum Corr), An Underutilized Fruit

Biochemical changes in wood apple fruit (Feronia elephantum Corr.) were studied at three different stages (unripe, semiripe, and ripe). Like most of the ripening fruits, the major changes observed were the increase in total sugars (3.2 to 4.9 g/100g) and decrease in acidity from (3.5 to 3.2 g/100g). Among the free sugars estimated by high performance liquid chromatography (HPLC), sucrose (0.85 g/100g) was predominant at all stages of ripening. Among organic acids, citric acid was detected as the major organic acid in the unripe (2.2 g/100g fresh weight basis (FW)) and ripe (1.6 g/100g FW) fruit. Unlike various other fruits, the total soluble solids were reduced upon ripening from 20.4 to 14.0. Brix. The total phenolics increased from 9.7 to 15.7 mg/g and the total protein also increased from 8.7 to 9.6 g/100g. It was also found that the wood apple contained more phenolics in the bound form than the free form. A high correlation was obtained between the reducing power and the total phenolic content.