title: Assessment of flavanol stereoisomers and caffeine and theobromine content in commercial chocolates.
abstract: Assessment of the flavanol composition of 41 commercial chocolates was by HPLC-DAD. Among individual flavonols ranged from 0.095 to 3.264mgg(-1), epicatechin was the predominant flavanol accounting for 32.9%. Contrary to catechin, epicatechin was a reliable predictive value of the polyphenol content. Conversely the percentage of theobromine used as a proxy measure for nonfat cocoa solids (NFCS) was not a good predictor of epicatechin or flavanol content. In a further chiral analysis, the naturally occurring forms of cocoa flavanols, (-)-epicatechin and (+)-catechin, was determined joint the occurrence of (+)-epicatechin and (-)-catechin due to the epimerization reactions produced in chocolate manufacture. (-)-Epicatechin, the most bioactive compound and predominant form accounted of 93%. However, no positive correlation was found with% cocoa solids, the most significant quality parameter.
authors.affiliation: Food and Nutritional Sciences Department, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, RG6 6AP Reading, United Kingdom. Electronic address: a.p.elena@reading.ac.uk.
authors.forename: M E
authors.initials: ME
authors.lastname: Alañón
authors.affiliation: Food and Nutritional Sciences Department, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, RG6 6AP Reading, United Kingdom.
authors.forename: S M
authors.initials: SM
authors.lastname: Castle
authors.affiliation: Food and Nutritional Sciences Department, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, RG6 6AP Reading, United Kingdom.
authors.forename: P J
authors.initials: PJ
authors.lastname: Siswanto
authors.affiliation: Food and Nutritional Sciences Department, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, RG6 6AP Reading, United Kingdom.
authors.forename: T
authors.initials: T
authors.lastname: Cifuentes-Gómez
authors.affiliation: Food and Nutritional Sciences Department, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, RG6 6AP Reading, United Kingdom.
authors.forename: J P E
authors.initials: JP
authors.lastname: Spencer
mesh_terms: D044946:Biflavonoids / Q000032:analysis; D002099:Cacao / Q000737:chemistry; D002110:Caffeine / Q000032:analysis*; D002392:Catechin / Q000032:analysis; D000069956:Chocolate / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005419:Flavonoids / Q000032:analysis*; D005504:Food Analysis; D059808:Polyphenols / Q000032:analysis; D044945:Proanthocyanidins / Q000032:analysis; D013237:Stereoisomerism; D013805:Theobromine / Q000032:analysis*; D014970:Xanthines / Q000032:analysis
chemical_list: D044946:Biflavonoids; D005419:Flavonoids; D059808:Polyphenols; D044945:Proanthocyanidins; D014970:Xanthines; C008514:methylxanthine; D002110:Caffeine; C017674:procyanidin; D002392:Catechin; D013805:Theobromine
keywords: Catechin; Chocolate; Epicatechin; Flavanols; Methylxanthines; Stereoisomers