Construction of Quality Evaluation Systems for Coffee Beans and Their Application to Chinese Coffee Beans

Abstract

In order to explore quality evaluation methods for Chinese coffee beans for freshly ground coffee and instant coffee and to select evaluation indicators, the major quality indicators were selected from the basic quality indicators through the Delphi evaluation method and sequence relationship analysis to construct a quality index system. Then the differences in the major quality indicators of 53 coffee bean samples from different production areas in Yunnan and Hainan provinces were determined, the characteristic quality indicators of coffee beans for different purposes were selected by correlation analysis, principal component analysis (PCA) and cluster analysis, and stepwise multiple linear regression analysis was conducted based on the comprehensive scores of the principal components of the samples. Finally, grain size, taste, aroma and carbohydrate content were selected as the characteristic quality indicators of instant coffee and grain size, taste, aroma and caffeine content as the characteristic quality indicators of freshly ground coffee. It is determined that the major varieties suitable for instant coffee are Catimor and Typica, and the major production area is Yunnan province. The major variety suitable for freshly ground coffee is Catimor, and the major production area is Yunnan province.

Keywords

• coffee beans; quality evaluation; principal component analysis; characteristic indexes; index screening