Differences in chemical characteristics due to different roasting of robusta coffee beans

Roasting is a process that contributes to the formation of compounds and flavors in coffee beans. Temperature length time are main factors roasting process. Generally, range temperatures times varies significantly for different varieties This study aims determine effect on changes chemical characteristics robusta beans (Coffea canephora) from Sidomulyo Village. used brewing methods brew roasted with best factorial randomized block design two factors: temperature, which consisted three levels (185, 190, 195 ⁰C), time, (10, 13, 16 minutes). The were analyzed water content, ash caffeine total phenol, pH. results this obtaineda content value 3.523 ± 0.129% 1.939 0.025%, 8.119 0.115% 4.315 0.260%, 2.494 0.015% 2.176 0.021%; phenol 6.251 0.101% 4.334 0.117%; pH 6.675±0.126 4.075±0.171. At stage, treatment (Zeleny method) produced by at 185⁰C 10 minutes. Robusta have moisture 0.129%; 2.494±0.015%; 6.251±0.101%; Key words: Coffea canephora; roasting; caffeine; phenol.