INFLUENCE OF CITRIC ACID, GINGER EXTRACT AND STORAGE PERIOD ON FRUIT QUALITY OF LOCAL ORANGE (Citrus sinensis L. Osbeck)

Abstract
This study was carried out on fruit of local orange (Citrus sinensis L. Osbeck) grown at private orchard Diyala governorate / Iraq, to study the effect of dipped fruits for 10 min in (0, 1, 2, 3% citric acid, 5 and 10% ginger) on fruit quality of orange during 65- and 105-days cold storage at 5+1 with 85- 90% RH. Dipping fruits in citric acid solution reduced fruit's weight loss and decay. Ginger extract at 5 and 10% significantly reserved acidity, total sugar and sugar/acid ratio, also caused a reduction in fruit weight loss and fruit decay. There was a significant decreases in fruits peel carotene and an increases in vitamin C, when fruits were treated with 5% ginger extract. Prolonging storage period from 65 to 105day significantly increased fruit total soluble solids, weight loss, total sugar, and fruit peel carotene but, reduced vitamin C and total acidity. The interaction between dip treatments and storage period had a significantly positive effect on the quality feature of fruit orange.