Simultaneous extraction of caffeine and chlorogenic acid from Arabica coffee using microwave-assisted extraction

This study aimed to optimize the microwave-assisted extraction (MAE) process for the selective decaffeination of Gayo Aceh Arabica coffee, focusing on the simultaneous reduction of caffeine (CF) and preservation of chlorogenic acid (CGA), while maintaining sensory quality and antioxidant potential. Response Surface Methodology (RSM) with a Face-Centered Central Composite Design (FCCD) was employed to evaluate the effects of microwave power (300–600 W), extraction time (2–10 min), and feed-to-solvent ratio (F/S) (0.100–0.150 g/mL). The optimal conditions were identified as 450 W microwave power, 10 min of extraction time, and a F/S of 0.125 g/mL. Under these settings, CF reduction reached 68.97 %, while 88.25 % of CGA was retained, resulting in a high selectivity ratio of 1.74. ANOVA and normal probability plot analyses confirmed the validity and predictive accuracy of the developed models. Compared to conventional decaffeination methods such as solvent-based or supercritical CO₂ extraction, MAE demonstrated superior efficiency, shorter processing time, and improved sustainability. Sensory analysis using the Kruskal-Wallis test showed no significant differences (p > 0.05) between decaffeinated and control samples in terms of aroma and taste acceptability. These findings highlight MAE as a viable, eco-friendly alternative for producing functional and specialty coffee products with preserved bioactive and sensory attributes.