Effects of Skin Coating Materials, Storage Conditions on PH,Titratable Acidity and Vitamin C Contents of Citrus Fruits Stored at Room and Refrigerated Temperatures

An investigation was carried out on fruits of five species of Citrus namely, Citrus sinensis, (sweet orange); C reticulate, (tangerine); C aurantium, (sour orange); C auratifolia, (lime); C paradise (grapefruit).The different citrus fruits were treated by dipping in a mixture of detergent solution and petroleum jelly and wrapping with aluminium foil and stored at room and refrigerated temperatures for 12 weeks.Control fruits which were not treated were also set up. The fruits treated by dipping in a mixture detergent solution and petroleum jelly and refrigerated showed the least changes in pH, highest changes in titratable acidity and lowest changes in vitamin C content. This was followed by fruits dipped in a mixture of detergent solution and petroleum jelly and refrigerated without wrapping.And the fruits treated by dipping in a mixture of detergent solution and petroleum jelly and stored at room temperature. All the treated fruits performed better when compared to the control with no treatment given and stored at room temperature.Regardless of treatment given to each fruit ,lime has the lowest pH, highest titratable acidity,this was followed sour orange, grapefruit, tangerine and sweet orange.As for the vitamin C content,sweet orange had the highest value, followed by sour orange, grapefruit,lime and tangerine in that order.