EFFECT OF MATURITY STAGE AND STORAGE DURATION ON PHYSICO-CHEMICAL PROPERTIES OF CITRUS (CITRUS SINESIS VAR. LATE VALENCIA)

Abstract

This study investigated the effect of maturity stage and duration of storage on physico-chemical properties of citrus fruits (Citrus sinensis var. late Valencia) in the Ashanti region of Ghana. A total of 450 mature fruits were harvested from the same farm for three different months, harvesting 150 fruits each month. Each harvest was categorised into three base on stage of maturity namely; mature green (MG), half ripe (HR) and full ripe (FR) fruits. A random sample of 50 fruits from the three categories were analysed on day one of harvest for their physico-chemical properties while the remaining 100 fruits were stored at ambient temperature (between 25C0 to 30C0) for 5 and 10 days before their physico-chemical properties were analysed. The physico-chemical properties measured were weight, juice yield, firmness, pH, vitamin C, TSS, sugar, TDS, TTA and EC. Some of the major findings of the study were that TTA in FR fruits were lower than that of MG and HR fruits at day five and ten of storage.Vitamin C content in MG, HR and FR fruits increased as storage duration increases to day five and ten under ambient temperature. Holding of MG and HR fruits for up to ten days increased the juice yield during processing compared to holding FR fruits. The study recommended that processors of natural orange juice should monitor closely the maturity stage of fruits they procure and the length of time fruits are stored before processing as product quality could be compromised or enhanced by these factors.