The separation of sodium, potassium, magnesium, and calcium on an Amberlite (H) column has been reported by Obara and Suzuki (4). The separation of iron and aluminum from each other, however, was not reported.By employing essentially the same technique with Dowex SOW, X-12, 200to 400-mesh, (H) form ion-exchange resins, the separation of the uniand bivalent cations was found to be complete. The separation of iron and aluminum was largely complete. The unresolved portions, if any, were small and did not alter the absorbances by a significant amount.The analytical scheme of Obara and Suzuki employs titration of the effluent acid from the column to determine sodium and potassium, complexometric titration with EDTA for magnesium and calcium, and two different colori-GRAPE JUICE FLAVOR metric schemes for iron and aluminum.To simplify the analyses, it was desirable to reduce the number of procedures involved. Sutton and Almy (<5) used an indirect chloride titration to determine magnesium and calcium after removal of the uncombined chlorides by evaporation. This method was found to be applicable for the determination of sodium, potasium, magnesium, and calcium.Molot and Kul'berg (2) reported the use of aluminen for the simultaneous determination of iron and aluminum. Iron was determined separately by the potassium thiocyanate method. It was found, however, that the suggested wave length of 530 µ did not correspond to the absorbance maximum of either iron (550 µ) or aluminum (525 µ).By combining and modifying the procedures of Molot and KuPberg (2). Obara and Suzuki (4), and Sutton and Almy (6), a simplified analytical scheme for all six cations was obtained.

A method is proposed for the detection of the adulteration of Concord grape juice with other anthocyanin-containing products. This method is.based on the aqueous separation of the monoglucosides followed by a densitometer tracing. An increase in the malvidin inonoglucoside content of the juice indicates the possibility of adulteration with the vinifera or hybrid varieties. To more specifically determine adulteration with hybrids, an evaluation of an increase in the diglucosidc content would be used as the criterion, primarily the large increase in the malvidin 3,5-diglucoside

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