Development of suitable method for the concentration of Citrus madurensis and Spondias dulcis juice

Abstract

Fruits are an excellent source of Vitamin C. Citrus madurensis (NasNaaran) and Spondias dulcis (Ambarella) are two tropical trees that bear fruits with high levels of Vitamin C, flavor and aroma compounds. Both fruits are currently under-utilized and therefore, this study was carried out to identify suitable method to concentrate their fruit juices while retaining the original qualities of the juices. The fruits were obtained from Maharagama in the Western province and juices were extracted by peeling and blending. The juices were concentrated by using Progressive Freeze Concentration (PFC), a novel non-thermal liquid food concentration method and evaporative concentration (Rotary Evaporation) method. The vitamin C content in the original juice and the concentrated juices were determined by spectrophotometerically at 521 nm. C.madurensis was concentrated up to brix 7.9o from brix 5.4o. S. dulcis was concentrated up to brix 9o from 6.9o using PFC and C. madurensis juice was concentrated up to brix 10.6o from 7.5o. S. dulcis was concentrated up to 10o brix from 7o from evaporative concentration. The initial vitamin C content in NasNaaran and Ambarella were 19.87 and 26.73 ppm respectively. Vitamin C loss for PFC method for C. madurensis and S. dulcis was 18.94% and 3.47% respectively. Vitamin C loss for evaporative concentration method for C. madurensis and S.dulcis was 73.67% and 29.24% respectively. Therefore, PFC is a suitable method to concentrate liquid fruit juice compare to conventional evaporative concentration.