Genetic diversity and correlation of bean caffeine content with cup quality and green bean physical characteristics in coffee (Coffea arabica L.)

Abstract BACKGROUND:Although people began to consume coffee for its stimulating effect, the demand for decaffeinated coffee is increasing and now accounts for 10% of the total amount of coffee consumed in the world. Forty‐two arabica coffee genotypes originating from Ethiopia were tested to assess caffeine content variability among them, and the correlation of caffeine content with cup quality and green bean physical characteristics. RESULTS:Green bean caffeine content was measured using high‐performance liquid chromatography, while cup quality was determined by professional coffee tasters. Caffeine content ranged from 9.1 to 13.2 g kg−1 on dry mass basis (d.m.b.). Six genotypes—AD0291, AD0591, AD2491, AD2691, AD2791 and AD2891—had a caffeine content of less than 10.0 g kg−1. Caffeine content showed negative and statistically significant correlations with cup quality attributes. Correlations between caffeine content and green bean physical characteristics were non‐significant. CONCLUSIONS:Simultaneous selection for low caffeine content and good cup quality is possible. Some accessions had low caffeine content, and may serve as a source of desirable genes for variety development of types with relatively low caffeine content. Copyright © 2008 Society of Chemical Industry