Effect of blend percentage and roasting degree on sensory quality of arabica-robusta coffee blend

Coffee is one of the most famous commodities in the world. There are two types of coffee planted in Central Aceh District, namely Arabica coffee andRobusta coffee. Robusta has a bitter taste and weaker aroma, while Arabica coffee has a slightly sour taste and strong aroma. Farmer in the area often mixsRobusta and Arabica coffee to produce a coffee blend that provide a better taste. However, the composition used in the blend is not known, so that there is no reference to make coffee blend withthe best quality. Beside blending, roasting also become one of the main factor influencingthe coffee's flavour. Therefore, it is necessary to investigate the effect of roasting degree and blend composition of Arabicaand Robusta coffee on its sensory quality. This research uses Randomized Block Design (RBD) Factorial with 2 factors. The first factor is the Arabica composition (P) with four levels, P1 = 0% Arabica, P2 = 10% Arabica, P3 = 20% and P4 = 30% Arabica. The second factor is the roasting degree (T) with three levels, ie T1 = light roasting, T2 = medium roasting and T3 = dark roasting.Results show that the coffee roasting degree has a very significant effect on pH and organoleptic and has no significant effect on total soluble solids of the coffee brew. As Arabica coffeepercentage was increased, the acidity of the coffee blend was also increases.Coffee blend with 20% Arabica with medium degree of roasting produces the highest total cup score and provides the best taste.