PERFORMANCE OF GRAPEFRUIT UNDER THE ECOLOGICAL CONDITIONS OF CENTRAL SUDAN .2. PHYSICOCHEMICAL EVALUATION OF FRUITS

The physical and chemical characters of fruits of 13 grapefruit (Citru s paradisi) cultivars were studied over the maturity period. Fruit wei ght increased with maturity and reached harvest size, 8-10 months afte r set. The edible portion (pulp) df the fruit increased; while the pee l (rind) decreased in both weight and thickness with ripening. Percent age juice content increased with maturity and by the age of 10 months, all cultivars produced the level of juice (35%) acceptable by the ind ustry. Both total soluble solids and sugar:acid ratio increased with m aturity. Significant differences in total acidity, which decreased wit h maturity, were observed among cultivars. Ascorbic, acid decreased wi th fruit maturity and significant differences were detected among the various cultivars. Reducing sugars, sucrose and total soluble sugars i n pulp and rind increased with ripening. After maturity was attained, there was an appreciable increase in reducing sugars, and a slight dec rease in sucrose, probably due to the inversion of sucrose to glucose and fructose.