Impact of Frozen Storage on the Anthocyanin and Polyphenol Content of American Elderberry Fruit Juice

The effects of frozen storage on the anthocyanin and polyphenol content of elderberry fruit juice are investigated. Juice from three genotypes of American elderberry (Adams II, Bob Gordon, and Wyldewood) was screened for total phenolic (TP) and total monomeric anthocyanin (TMA) content with spectrophotometric methods. The individual anthocyanin content (IAC) of the juice was tested by coupling solid phase extraction with ultra-performance liquid chromatography/tandem mass spectrometry. Juice samples were tested initially upon harvest, then again after 3, 6, and 9 months of frozen storage. Juice from the three different genotypes had significantly different TP, TMA, and IAC profiles initially (p