Apple Leucoanthocyanins

Abstract

SUMMARY The leucoanthocyanins present in the peel and flesh of Gravenstein apple were extracted with methanol and fractionated. Five preparations were obtained from apple peel, and three from apple flesh. These were characterized on the basis of solubility, mobility on paper, astringency and nature of products yielded on heating with dilute and concentrated hydrochloric acid solutions. On mild acid hydrolysis both the peel and flesh leucoanthocyanins yielded catechin and epicatechin. On stronger acid hydrolysis these yielded cyanidin and pelargonidin. Absorption spectra were obtained in the visible, ultraviolet, and infrared regions. The major apple leucoanthocyanins were found to be highly polymerized and quite complex.