Separation Techniques

Biography

Biography: Jong-Sup Jeon

Abstract

Coffee has been for decades the most commercialized and widely consumed beverage in the world. Coffee beans contain a large variety of substances, which in many cases are biologically active, such as caffeine and chlorogenic acids. Chlorogenic acids are water-soluble phenolic components of coffee and other plants formed by the esterification of certain trans cinnamic acids, such as caffeic, ferulic and p-coumaric acids,with(-)-quinic acid. The main subgroups of chlorogenic acid isomers in coffee are the caffeoylquinic acids, feruloylquinic acids, dicaffeoylquinic acids and, in smaller amounts, p-coumaroylquinic acids. In this study, we carried out robustness evaluation for method validation of quantification of chlorogenic acid in coffee brew, using Youden’s test. It was possible to determine the effect of each analytical parameter in the final analysis results. Seven analytical factors were selected and small variations were induced in the nominal values of the method. Then, 8 runs were performed aiming to determine the influence of each parameter in the final result. The 7 factors are: Concentration of KH₂PO₄ in mobile phase, column temperarture, flow rate, wavelength of detector, column supplier and initial mobile phase composition. Standard deviation of the differences Di (SDi) was calculated and that value was not larger than the standard deviation of the method carried out under within-laboratory reproducibility conditions. The experimental t values resulted below the 2-tailed t-critical value for all 7 factors. The tested procedure proved to be fairly robust since minor fluctuations in the operative parameter that can occur during the routine application of the method do not significantly affect its performance characteristics.