Characterization of primary standards for use in the HPLC analysis of the procyanidin content of cocoa and chocolate containing products.
This report describes the characterization of a series of commercially available procyanidin standards ranging from dimers DP = 2 to decamers DP = 10 for the determination of procyanidins from cocoa and chocolate. Using a combination of HPLC with fluorescence detection and MALDI-TOF mass spectrometry, the purity of each standard was determined and these data were used to determine relative response factors. These response factors were compared with other response factors obtained from published methods. Data comparing the procyanidin analysis of a commercially available US dark chocolate calculated using each of the calibration methods indicates divergent results and demonstrate that previous methods may significantly underreport the procyanidins in cocoa-containing products. These results have far reaching implications because the previous calibration methods have been used to develop data for a variety of scientific reports, including food databases and clinical studies.
Hurst
William J
WJ
The Hershey Center of Health and Nutrition, The Hershey Company, 1025 Reese Avenue, Hershey, PA 17033, USA. whurst@hersheys.com
Stanley
Bruce
B
Glinski
Jan A
JA
Davey
Matthew
M
Payne
Mark J
MJ
Stuart
David A
DA
D044946:Biflavonoids / Q000032:analysis*; D002099:Cacao / Q000737:chemistry*; D002392:Catechin / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000592:standards*; D044945:Proanthocyanidins / Q000032:analysis*; D012015:Reference Standards; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D044946:Biflavonoids; D044945:Proanthocyanidins; C017674:procyanidin; D002392:Catechin