Red raspberry wine was made from thawed fruit by fermentation of pulp, depectinized juice, and pasteurized depectinized juice. The influences of fining and storage were also investigated. The anthocyanin pigment profiles of the samples were determined by high performance liquid chromatography (HPLC), and additional color indices by spectrophotometry and Hunter calorimetry. Anthocyanin pigments degraded mainly during fermentation, with total losses after storage of at least 50%. Cyanidin-3-glucoside was the most unstable anthocyanin, disappearing completely during fermentation; cyanidin-3-sophoroside (the major anthocyanin) was the most stable pigment. Pasteurized, depectinized wine that had undergone fining, had the most stable color and best a@pearance after storage.

Blackberry wine was made from thawed fruit (Evergreen variety) by fermentation of pulp, depectinized juice, and high-temperature shorttime (HTST)-treated and depectinized juice. The effects of fining and storage on pigment composition, color and appearance were investigated. Seven anthocyanin pigments (cyanidin-3-glucoside, cyanidin-3-rutinoside, a xylose-cyanidin derivative, two acylated cyanidin derivatives, cyanidin and a polymeric derivative) were detected in the juices and wines by HPLC. Cyanidin-3-glucoside was highly unstable during fermentation. Haze development and sediment formation occurred, and 8.5 to 100% of total anthocyanins degraded. Blackberry juice that had been HTST-pasteurized, depectinized and fined produced wine with the most stable color and best appearance after storage.

Acid and base hydrolysis simplified the complex HPLC chromatographic profile of red raspberry juice phenolics dramatically. In three acid-hydrolyzed juices, ellagic acid, two unidentified ellagic acid compounds, and gallic, p-hydroxybenzoic, protocatechuic, caffeic, p-coumaric, and ferulic acids, as well as (+)-catechin, (-)-epicatechin, quercetin, and kaempferol were separated and identified using HPLC diode array spectral techniques. The percentages of HPLC peak area for these phenolics were similar in the acid-hydrolyzed juices. In base-hydrolyzed samples the same phenolics, except the second ellagic acid compound, were present, and the first ellagic acid compound was present in smaller quantity. Sep-Pak CU cartridges were used for sample preparation. Hydrolysis could become a very useful tool for rapidly screening raspberry juices for qualitative deviations from authentic HPLC profiles to determine adulteration by other fruit juices or phenolic mixes.

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