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JAMA. 1948;136(6):402. doi:10.1001/jama.1948.02890230042013.
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UTILIZATION OF ASCORBIC ACID  With the advent of vitamins in chemically pure form, the question has naturally arisen regarding the comparative nutritive value of the natural versus the synthetic forms of vitamins. Not only has there been presumptive superiority of certain of the vitamins as they occur in natural fruits and grains, but a recent report1 describes the considerably greater vitamin C (ascorbic acid) potency of natural and fortified orange juices when assayed by the dental biologic assay than could be accounted for by the ascorbic acid determined therein by quantitative chemical analysis. Melnick and his co-workers2 have thrown light on this general problem by reexamining the comparative stability of ascorbic acid in aqueous solution and in apple juice. Under controlled conditions of hydrogen ion (PH) and initial concentration, the vitamin C in apple juice is far more stable when stored at high summer temperature than is

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