Effect of altitude, stages of maturity and Processing methods on the physical and cup quality Attributes of coffee (coffea arabica l.) At teppi green Coffee farm

Abstract

Modern coffee plantations contribute to about 5-8% of the total production in the country and most of them are found in southwestern. The areas are endowed with diverse and suitable enviroments, which have potential to produce quality coffee that can meet the preference of consumers. The farms are established mainly to produce washed quality coffee with sustainable yield. But, some of the varieties which are high yielder and adapted to these areas have maturity problems. Thus, the objectives of this experiment were to evaluate the influence of altitude (law, medium and high land), stages of maturity (light green, yellow and red cherries)) and processing methods (wet, semi-wet and dry) on the physical and cup quality attributes of Arabica coffee variety. Accordingly, the experiment was conducted at Tepi Green Coffee Plantation from October 2011 to June 2012 using a 3×3×3 factorial experiment arranged in randomized complete block design (RCBD) with three replications. Physical and cup quality parameters were recorded and analyzed using SAS version 9.2 software package. The light green, yellow and red ripe cherries were handpicked from three study sites and evaluated under three processing methods.The results showed significant variations due to altitude, stages of maturity and processing methods for most coffee quality traits. In addition, the interaction effects between the treatments such as shape and make, color, total raw quality and body were significant. Accordingly, the red and yellow stages of maturity were superior and did not show significant difference at all the three altitudes for the total quality. With regard to processing methods, the wet method significantly improved the raw and cup quality over the other practices and resulted in better total quality. Coffee quality improvement due to processing techniques increased in order of dry method, semi-washed and wet method. With regard to altitude, the variety was noted to be more specific to Anderacha high land in terms of its quality, largely due to the influence of microclimate though the variety had unique characteristics in adapting at all sites. Because of this, the 7454 variety remains the best alternative for coffee growing areas of Teppi and Godare. From the present findings, it can be concluded that the quality of the variety can be maximized by harvesting at the red and yellow stages and using the wet method. However, further studies should be progressed mainly in analyses of bio-chemical constituents, nutrient levels, tree management, climate condition at different stages of cherry development and different shade conditions.