SUMMARY– A new method was developed to determine the quantities of the four major anthocyanins in cranberry and cranberry products. The pigments were streaked on Whatman No. 1 paper and separated by multiple ascending chromatography with 1‐butanol‐benzene‐formic acid‐water (100:19: 10:25). The individual bands were measured by transmission densitometry at 525 nm. The ratio of individual pigments was calculated from the densitometric peak areas. The linearity of densitometric response for anthocyanins was established. The amount of each individual anthocyanin present was calculated from the total anthocyanin content and the ratio of individual anthocyanins. The reproducibility of the methods was 6% for the two arabinosides and 4 to 5% for the two galactosides expressed as the coefficient of variability.

The aim of the presented work was to study the effect of pressing method, pasteurization, cultivar, and vintage on the content of (+)-catechin, (-)-epicatechin, and nine procyanidins in grape juice. The results showed that the concentration of these flavan-3-ols in the juice was influenced, in decreasing order of importance, by pressing method, cultivar, pasteurization, and vintage. Cold pressing without maceration was the least and hot pressing after maceration at 60 degrees C for 60 min the most effective method for extracting the flavan-3-ols. Pasteurization increased the concentration of catechins in cold-pressed juices, but it decreased concentrations in hot-pressed juices. The concentration of most procyanidins was increased by pasteurization. Among the white cultivars, Seyval and Niagara were highest in procyanidins and Elvira and Chardonnay were highest in catechins. Vincent, Foch, and Baco were the red cultivars highest in catechins, and Vincent also had the highest content of procyanidins.

SUMMARY— The method developed consists of extracting the anthocyanins with ethanol‐1.5N hydrochloric acid (85:15) and measuring the O.D. of the extract, diluted with the extracting solvent, at 535 nm. The total anthocyanin content was calculated in absolute quantities with the aid of the extinction coefficients established for the four major cranberry anthocyanins dissolved in the alcoholic solvent system.

SUMMARY— The method developed for total anthocyanin determination involves the measurement of the absorbance at 510 nm on samples diluted with pH 1.0 and 4.5 buffers. The pigment content is calculated in absolute quantities with the aid of extinction coefficients established for the cranberry anthocyanins dissolved in the buffers. An index of anthocyanin degradation, based on a new concept, could be calculated from the measurements obtained for the total anthocyanin determinations.