Effects of variety and moisture content prior to artificial drying on raw and cup quality of coffee (Coffea arabica.L) at gemadro coffee plantation

Abstract

With respect to the maintenance of coffee quality, drying is the most critical post-harvest processing step. This step is crucial since it will dictate quality performance of coffee. The objective of this study was to evaluate variations in terms of quality of coffee subjected to mechanical drying with different initial moisture contents (21, 40 and 60 percent) and determine appropriate initial moisture content of parchment coffee for mechanical drying of different coffeevarieties. Red ripe cherries of six different varieties (744, 7454, 74110, 74112, 74165, 75227) and one control treatment (local method of working at Gemadro coffee plantation by mixing all varieties) were harvested and processed from Gemadro coffee plantation and examined for physical and sensory attributes with factorial complete randomized design. Accordingly, findings of the study revealed significant variations for all coffee raw quality attributes. Moisture content and variety had significant effect on primary defect, secondary defect and shape and make while Color, odor and raw qualities were significantly affected by the interaction of the two. ANOVA result for Cup quality showed all cup quality attributes except cup cleanness were affected by variety and moisture content and interaction effect was significant for acidity and specialty value. The result pertaining to raw quality depicted that coffees pre-dried to as low as 21 percent moisture content had higher raw quality value for most varieties whereas,the poorest raw quality value was recorded for coffees dried directly by mechanical drier without any pre-drying. The cup quality value also indicated that higher coffee quality with sweet balanced cup was recorded for most coffee varieties pre-dried to 21 and 40 percent moisture content before mechanical drying and coffee varieties dried mechanically without sun drying recorded poor or fair cup values. From the present findings, it could be concluded that pre-drying coffee to reduce initial moisture content will help to preserve the inherent quality of coffee.