Organic acid and sugar contents in different domestic fruit juices

Organic acid and sugar contents in ten kinds of juices (two orange juices, two grape juices, two aloe juices, two citron juices, one bokbunja, and one grapefruit juice) were analyzed by high-performance liquid chromatography. Citric acid was detected in all the fruit juices analyzed. Grape juices contained the highest tartaric acid content (67.85 - 99.37 mg/100 mL) while orange and grape juices contained a high content of malic acid (151.67 - 211.18 mg/100 mL). Lactic acid was detected in all the aloe juices (35.12 - 65.27 mg/100 mL) as well as in one orange (203.8 mg/100 mL) and one grape juice (112.28 mg/100 mL). Citrus fruit juices (A, A', F) showed the highest content of total organic acids as 902.81 - 1,103.7 mg/100 mL. With regard to sugar contained in the juices, lactose and maltose were not detected in any of the fruit juices. Even when comparing the same kind of fruit juice, sugar (fructose, glucose, and sucrose) content showed a significant difference (p < 0.05) depending on the manufacturer. In the grape juices, contents of fructose (6.86 - 7.51) and glucose (6.23 - 7.3 g/100 mL) were higher than in other juices. One serving size of the juices (180 mL) analyzed in this study can provide approximately 3.3 - 4.9% of total daily energy requirements when consumed as part of the 2,200 kcal/day diet required for an adult.