Determination of reducing and total sugars in West Indian cherry (malpighia punicifolia, L.) juice

Abstract

(1) Ascorbic acid is the substance responsible for the discrepancies found in the determination of reducing sugars and total sugars by the Lane-Eynon method. By correcting for ascorbic acid using the factor (F) 0.686, the discrepancy is eliminated and the Lane-Eynon method can be used. (2) To determine the total sugar content of West Indian cherry juice corrected reducing sugars only need be assayed, because it was proved experimentally and statistically that there is no significant difference between corrected reducing and corrected total sugars. (3) The sugar content of West Indian cherry juices stored at room temperature and at 45°F. does not change appreciably after 1 year. (4) At 45°F. ascorbic acid is lost less readily than at room temperature, but temperature produces no significant difference in the true sugar content of the juice.