Related Experiment Video
Updated: Apr 11, 2026

Post Column Derivatization Using Reaction Flow High Performance Liquid Chromatography Columns
Published on: April 26, 2016
Analysis of Cocoa Proanthocyanidins Using Reversed Phase High-Performance Liquid Chromatography and Electrochemical
Todd H Stanley1, Andrew T Smithson2, Andrew P Neilson2
1†Department of Food Science, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.
Abstract:
Flavan-3-ols and proanthocyanidins play a key role in the health beneficial effects of cocoa. Here, we developed a new reversed phased high-performance liquid chromatography-electrochemical detection (HPLC-ECD) method for the analysis of flavan-3-ols and proanthocyanidins of degree of polymerization (DP) 2-7. We used this method to examine the effect of alkalization on polyphenol composition of cocoa powder. Treatment of cocoa powder with NaOH (final pH 8.0) at 92 °C for up to 1 h increased catechin content by 40%, but reduced epicatechin and proanthocyanidins by 23-66%. Proanthocyanidin loss could be modeled using a two-phase exponential decay model (R(2) > 0.7 for epicatchin and proanthocyanidins of odd DP). Alkalization resulted in a significant color change and 20% loss of total polyphenols. The present work demonstrates the first use of HPLC-ECD for the detection of proanthocyanidins up to DP 7 and provides an initial predictive model for the effect of alkali treatment on cocoa polyphenols.
More Related Videos
13:35A Convenient Method for Extraction and Analysis with High-Pressure Liquid Chromatography of Catecholamine Neurotransmitters and Their Metabolites
Published on: March 1, 2018
14:39Semi-Targeted Ultra-High-Performance Chromatography Coupled to Mass Spectrometry Analysis of Phenolic Metabolites in Plasma of Elderly Adults
Published on: April 22, 2022
Related Concept Videos
Electrophoresis: Overview
There...
High-Performance Liquid Chromatography: Types of Detectors
High-Performance Liquid Chromatography: Introduction
In HPLC, two phases play a critical role in the separation process:
Ion-Exchange Chromatography
High-Performance Liquid Chromatography: Instrumentation
Capillary Electrophoresis: Instrumentation