title: Flavanol and procyanidin content (by degree of polymerization 1-10) of chocolate, cocoa liquors, cocoa powders, and cocoa extracts: first action 2012.24.
abstract: An international collaborative study was conducted on an HPLC method with fluorescent detection for the determination of flavanols and procyanidins in chocolate and cocoa-containing materials. The sum of the oligomeric fractions with degree of polymerization 1-10 was the determined content value. Sample materials included dark and milk chocolates, cocoa powder, cocoa liquors, and cocoa extracts. The content ranged from approximately 2 to 500 mg/g (defatted basis). Thirteen laboratories--representing commercial, industrial, and academic institutions in six countries--participated in this interlaboratory study. Fourteen samples were sent as blind duplicates to the collaborators. Results for 12 laboratories yielded repeatability RSD (RSDr) values below 10% for all materials analyzed, ranging from 4.17 to 9.61%. Reproducibility RSD (RSDR) values ranged from 5.03 to 12.9% for samples containing 8.07 to 484.7 mg/g material analyzed. In one sample containing a low content of flavanols and procyanidins (approximately 2 mg/g), the RSDR was 17.68%.
authors.affiliation: Mars Chocolate North America, Analytical and Applied Sciences Group, Mars, Inc., 800 High St, Hackettstown, NJ 07840, USA.
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Robbins
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Leonczak
authors.forename: Julia
authors.initials: J
authors.lastname: Li
authors.forename: J Christopher
authors.initials: JC
authors.lastname: Johnson
authors.forename: Tom
authors.initials: T
authors.lastname: Collins
authors.forename: Catherine
authors.initials: C
authors.lastname: Kwik-Uribe
authors.forename: Harold H
authors.initials: HH
authors.lastname: Schmitz
mesh_terms: D044946:Biflavonoids / Q000032:analysis*; D002099:Cacao / Q000737:chemistry*; D002392:Catechin / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005419:Flavonoids / Q000032:analysis*; D010936:Plant Extracts / Q000032:analysis*; D011208:Powders; D044945:Proanthocyanidins / Q000032:analysis*; D015203:Reproducibility of Results
chemical_list: D044946:Biflavonoids; D005419:Flavonoids; D010936:Plant Extracts; D011208:Powders; D044945:Proanthocyanidins; C017674:procyanidin; D002392:Catechin