Identification of chlorogenic acid content of coffee from Klungkung Jember Plantation based on roasting temperature variations

Abstract

This study aims to determine the content of chlorogenic acid in pure and mixed roasted Arabica and Robusta coffee. Coffee samples were selected from the Klungkung Jember Plantation and then roasted using various times and then the absorbance was observed to obtain information on the chlorogenic acid content. The absorbance value of chlorogenic acid in the sample is known based on the maximum absorption wavelength of the standard solution of chlorogenic acid at a wavelength of 200-400nm UV-Vis Spectrophotometer. The coffee was roasted for 7 minutes at various temperatures that are 195°C, 215°C and 240°C. The used materials for mixture coffee are soybean and corn, respectively, with the fractions of 10%, 20%, 30%, and 40%. Measurement of chlorogenic acid was conducted to the pure coffee samples of arabica coffee and robusta coffee. The measurements were also done to the mixed coffee, namely Arabica coffee mixed with soybeans with the above fractions at all three roasting temperatures. The sam same measurements were repeated to the mixture of robusta coffee and corn. The results showed that the content of chlorogenic acid is proportional to the content of the coffee fraction in the mixture, both in a mixture of Arabica coffee with corn and soybeans. Likewise, the mixture of robusta coffee with corn and soybeans have similar pattern. Meanwhile, the roasting temperature variations showed that higher roasting temperatures produced lower chlorogenic acid and the coffee mixed with soybeans has a higher chlorogenic acid content compare to the corn mixture material.