الفهرس 
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Abstract
The results obtained to this investigations revealed that Thompson Seedless grape variet1 produced higher percent in juice yield sod T . S . S . than Italian and Rozaki varieties . This ’may be ascribed to the fact that this variety has no seeds and all the berries content are fleshy .
The data show that Rozaki grape juice has high values in total acidity , total sugars , and ash content . But Italian grape juice produced lower values to total acidity total sugars and T. S . S., while it had higher value to the vitamin C content .
The variations in the chemical composition of’ the different grape varieties are mainly due to the difference in heredity between these varieties .
Studying the effect of pasteurization , type of containers and storage time on the chemical properties of t he three grape varieties revealed that T. S . S Total acidity t non- reducing sugars , and vitamin C content were gradually decreased as the storage period increase ,but the reduction 1n ell these values we’re higher in cans container compared to the bottles ones .on the other band ,the data indicated that there is a slightly increase in the reducing sugars by increasing the storage period of juice . This may be due to inversion of non- reducing sugars to reducing sugar s as b result of original organic acids present
In juices and fluctuate of room temperature during storage . Also , data show that the ash content in stored juices fluctuate t o stable ’in both typo continers .
Generally , data revealed that there were ’marked changes in the chemical composition of the pasteurized grape juioes during storage period in the case of can container than in the bottles ones. ’I:his may be due to the type of co nta1Der during storage . The organo1eptic properties of Rozai juice was gradually decreased during storage period than in both Thompson seedless and Italian grape juices.