Total anthocyanin and total phenolics were determined on these extracts. Total monomeric anthocyanin content of the different extracts was determined by pH differential method (Spectrophotometric method). Total monomeric anthocyanin was expressed as cyanidin-3-glucoside. Total phenolics were determined by Folin-Ciocalteu method (Spectrophotometric method) on the extracts. A gallic acid standard was used, and was expressed as gallic acid equivalent.

The effectiveness of heat, SO2, and acidity in extracting these compounds from processing waste will be performed on a bench-top scale. These treatments will be applied individually and in combination. Total monomeric anthocyanin and total phenolics will also be performed on these samples. From the bench-top study, parameters that had the greatest yield of anthocyanins and phenolics will the chosen to perform pilot-plant processing of whole blueberries, and presscakes, into extracts. Major efforts will be directed towards determining the specific anthocyanin and polyphenolic content of samples obtained by each treatment, or treatment combination. Individual, and total, anthocyanin and polyphenolics by High Performance Liquid Chromatography (HPLC) will be performed on these extracts. Antioxidant measurements will be performed by Ferric Reducing Antioxidant Potential (FRAP), and Oxygen Radical Absorbance Capacity (ORAC). Total monomeric anthocyanin, and total phenolics by spectrophotometric methods, color measurements by Hunter Colorimeter, and a stability study will also be conducted on the samples obtained by the pilot plant processes.

Huckleberries (V. membranaceum, V. ovalifolium, and V. delisciosum) from the Pacific Northwest were grown at USDA, Agricultural Research Service, National Clonal Germplasm Repository (Corvallis, OR). Huckleberries were harvested (June 11 to July 8, 2002) from this plot according to their ripeness. Anthocyanin and phenolic (flavonols, procyanidins, cinnamates) composition of these huckleberries will be examined in the future.