Selective green extraction of caffeine and chlorogenic acid from robusta coffee beans for the development of functional ingredients

Coffee is a widely consumed beverage with a distinctive flavor that provides stimulating effect on body. It contains bioactive compounds that increase alertness and are beneficial for health. However, for individuals who are sensitive to caffeine, excessive consumption may cause adverse effects. This study aimed to determine the most effective decaffeination method and evaluate the feasibility of solvent purification to improve the sustainability of the coffee production process. Decaffeination was carried out using a direct solvent extraction method with ester-based solvents (ethyl acetate, amyl acetate and ethyl butyrate). The effects of extraction time, temperature, and coffee to solvent ratio on the reduction of caffeine and chlorogenic acid were investigated. The results showed that ethyl acetate was the most effective solvent for decaffeination. Under effective conditions (90 min, 25 °C, and a coffee to solvent ratio of 1:1:5), caffeine content was reduced by 99.880 ± 0.098% (w/w), while chlorogenic acid decreased by 52.250 ± 0.156% (w/w). Moreover, the solvent purification process confirmed that ethyl acetate could be recovered and reused, thereby reducing chemical waste, lowering production costs, and minimizing dependence on new solvents. These supports a more sustainable and efficient decaffeination process that contributes to the development of functional coffee ingredients, such as chlorogenic acid and caffeine, with antioxidant properties and health benefits.