title: An industry consensus study on an HPLC fluorescence method for the determination of (±)-catechin and (±)-epicatechin in cocoa and chocolate products.
abstract: BACKGROUND
  This manuscript describes the results of an HPLC study for the determination of the flavan-3-ol monomers, (±)-catechin and (±)-epicatechin, in cocoa and plain dark and milk chocolate products. The study was performed under the auspices of the National Confectioners Association (NCA) and involved the analysis of a series of samples by laboratories of five member companies using a common method.
  
  
  METHODS
  The method reported in this paper uses reversed phase HPLC with fluorescence detection to analyze (±)-epicatechin and (±)-catechin extracted with an acidic solvent from defatted cocoa and chocolate. In addition to a variety of cocoa and chocolate products, the sample set included a blind duplicate used to assess method reproducibility. All data were subjected to statistical analysis with outliers eliminated from the data set.
  
  
  RESULTS
  The percent coefficient of variation (%CV) of the sample set ranged from approximately 7 to 15%.
  
  
  CONCLUSIONS
  Further experimental details are described in the body of the manuscript and the results indicate the method is suitable for the determination of (±)-catechin and (±)-epicatechin in cocoa and chocolate products and represents the first collaborative study of this HPLC method for these compounds in these matrices.
authors: National Confectioners Association, 1101 30th St NW, Suite #200, Washington, DC 20007, USA. laura.shumow@candyusa.com.
authors: Laura
authors: L
authors: Shumow
authors: Alison
authors: A
authors: Bodor