Some physicochemical parameters of orange juice from seven orange varieties (Pineapple orange,Hamlin,Trovita,Jincheng,1232 Tangor,Olinda Valencia,and Delta Valencia) were analyzed,special attention was paid to the level of sugars,organic acids,free amino acids,mineral composition,and color parameters. The results showed that total soluble solids (TSS),TSS/titratable acidity (TA) ratios,sugars,and organic acids were kept within a proper range for juice processing except that Jincheng had lower TSS than the others. Sucrose was the most dominant sugar in the orange cultivars,followed by fructose and glucose,while citric acid was the principal organic acid. Serine and proline were the principal amino acids. Potassium was the most abundant mineral in all of the juice samples,followed by magnesium and calcium. The sodium content of most varieties was under 10 mg kg-1. Though all of the samples had orange colour,Olinda Valencia and Delta Valencia had deeper red colour than the others. Statistically significant differences (P < 0.05) were found between the samples in most of the characteristics. The results provided important information on the physicochemical characteristics of the varieties and on how to make the best use of orange cultivars for different purposes,which is of significance for both technological research and processing practice.
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