Effects of Using Controlled Decafeinated Machine on Quality of Robusta Coffee Bean

The objective of this research is to determine the effects of residence time during decaffeination process using ethyl acetate solvent in decaffeinated controlled machine. The residence times are 2, 4 and 6 h. Decaffeination process was divided into two steps. First step was steaming process and the second step was caffeine extraction process. The objective of steaming process was to achieve the maximum moisture content of coffee bean, so the ethyl acetate solvent could penetrate the coffee bean. The results of steaming process of Robusta coffee beans in the decaffeinated controlled machine for 4 h indicated resources that the beans and their water adsorbed moisture content Increased from 12 to 52%. At the second step, the beans experienced Darkening of color indicated resources by the decreasing value of L from coffee bean. The Lowest caffeine content of 0.3% gained from the longest residence time of decaffeination process (6 h). Decaffeinated coffee bean has the value of the organoleptic test are in the range of 2-2.5 for aroma, flavor, bitterness and body.