Isolation and identification of procyanidins in apple pomace

The chemical nature of the procyanidin components in apple pomace was inves tigated as part of a programme seeking alternative uses of the large quanti ty of pomace that is being generated from the apple juice industry. The hom ogeneous nature of the procyanidin fractions was demonstrated by the isolat ion and identification of a range of epicatechin oligomers, namely epicatec hin-(4 beta-6) epicatechin, epicatechin (4 beta-8) epicatechin, epicatechin (4 beta-8) epicatechin (4 beta-8) epicatechin and epicatechin (4 beta-8) e picatechin (4 beta-8) epicatechin (4 beta-8)-epicatechin. The procyanidin p olymers were also isolated and purified by a Sephadex LH20 column and shown to consist exclusively of epicatechin units. The chemical structures of th ese procyanidins were established by C-13-NMR spectroscopy, by acid-catalys ed degradation reaction with phloroglucinol and by electrospray mass spectr ometry. (C) 1999 Elsevier Science Ltd. All rights reserved.