1.1 Economic Importance of Fruit Juice
Fruit juice is a ready and rich source of vitamins, fibre and mineral salt for human consumption due to its uses as medicine, food and appetites (Ashurt, 1991). Fruit juice is originally produced as a result of surplus production of fruits, but it is obtained from processing specially grown species for that purpose. Juice obtained from citrus fruits like orange (Citrus sinensis), tangerine (Tamarinds indica), grape (Citrus pavadisi), lemon (Citrus Limon), and lime (Citrus oryantifolia) dominate the market. Other main sources of juice are pineapple (Ananas comosus), mango (Mangifera indica), water melon (Citrulus lanatus), pine apple (Ananas comosus), Cashew (Anacardium occidentale) and others.
Fruits are difficult to keep for a considerable length of time, thus ripe fruits are utilized either as fresh fruit or processed into juice and specialty products. Most fruits are perishable in their natural state after harvest; deterioration sets in almost immediately due to metabolic activities which continue even after harvest. The perishable nature makes it difficult to store and preserve fruits; hence there is gradual loss of flavour and nutritional values. Large quantities of fruits are produced and wasted in Nigeria and many other developing tropical countries. It is highly essential to process and preserve the fruits in order to guarantee regular supply at affordable prices. Hence, there is a need to develop equipment for effective extraction of juice from fruits in order to reduce post harvest wastage and thereby ensure an all-season availability of juice at reasonable costs.