Biochemical Composition of Green Coffee Beans as Geographic Indication in Ethiopian Specialty Coffees

Abstract

Biochemical composition of green coffee beans can be used as reliable geographical indicators to characterize quality. No efforts have been made in Ethiopia to elucidate the biochemical composition of green coffees based on geographical origin. The objective of this research was to determine the biochemical composition of green coffee beans in Ethiopia based on location. Green coffee beans were obtained from three replicated sites per farm from a total of 24 farms in south-western (SW), western (W), southern (S), north-western (NW) and eastern (E) major coffee growing regions of Ethiopia. Handpicked coffee cherries at peak maturity were used for the study during the 2010/2011 growing season. The study followed a multistage purposive random sampling method in a nested design. The results of the study revealed that location significantly (P<0.05) affected the values of caffeine, 5-CQA (5-Caffeoylquinic acid), Feruloylquinic acids (FQA), 3,4-Dicaffeoylquinic acids (3,4-DCQA) and 4,5-Dicaffeoylquinic acids (4,5-DCQA). Green coffee bean composition of 4-CQA (4-Caffeoylquinic acid), 5-CQA, 4,5-DCQA, caffeine, FQA, and 3-CQA in a descending order of importance contributed much to separate coffees originating from the eastern region distinctly from those originating from both the western and southern regions. However, 4-CQA, 3-CQA (3-Caffeoylquinic acid), FQA, 4,5-DCQA, 5-CQA, and caffeine in their descending order of importance contributed much to separate coffees originating from the south-western region from those originating from both the southern and north-western regions. However, a repeated and an integrated study is sought to come to a comprehensive conclusion and recommendation.