Influence of genotype and processing on bioactive compounds of Ethiopian specialty Arabica coffee

Ethiopian specialty coffee is exported to the international market based on the cup quality classification; however, there is limited information on the chemical characteristics. In this study, dry and wet-processed sixteen Ethiopian specialty coffee genotypes were investigated for total polyphenols, chlorogenic acids, caffeine, and trigonelline at different stages using UV-Vis spectrophotometric and Rapid Separation Liquid Chromatographic methods. Cup qualities of green coffee beans and brewed coffee were also assessed by professional cuppers. The results indicated that the bioactive compounds and cup qualities were significantly influenced by genotypes, green bean processing methods, and medium roasted-ground and brewed coffees. It was shown that the percentage of reduction in total polyphenols, chlorogenic acids, caffeine, and trigonelline concentrations were 77.3%, 82.5%, 47.8%, and 70.6%, respectively as the beans are transformed to brew. This study also fills the gap of information on the influence of processes and correlation to cup quality with bioactive compounds.