Abstract
This study aimed to investigate changes in the diverse compound in coffee beans under different roasting conditions. Four different kinds of chemical characteristics (phenolic contents, flavonoid contents, chlorogenic acid, and caffeine) were analyzed. According to the temperature of coffee roasting, this study categorized green bean, extract A ($191^{\circ}C$), B ($202^{\circ}C$), C ($220^{\circ}C$), and D ($233^{\circ}C$). As a result, total phenol compound showed low level of total phenol compound at lower temperatures. Extract A showed significantly higher level of total flavonoid ($111.33{\pm}10.14$), green bean showed $83.67{\pm}2.43$, Extract B $46.11{\pm}2.38$, C and D showed $31.44{\pm}0.12$, $19.22{\pm}0.46$ respectively. Green bean showed higher level of chlorogenic acid ($64.47{\pm}0.51$), Extract A ($39.66{\pm}0.47$), extract B ($12.45{\pm}0.99$), C, D ($3.59{\pm}0.31$, $0.63{\pm}0.12$) respectively. This study also noted that there are significant different in terms of caffeine content. Extract A has higher level of caffeine content ($38.45{\pm}1.70$) significantly, green bean ($27.14{\pm}2.27$), extract B ($18.95{\pm}0.64$), extract C ($17.89{\pm}0.96$). As a conclusion, we revealed that roasting conditions play an important role in the composition of coffee compounds.