Optimization of the brewing parameters on coffee extraction using a central composite rotatable design.

Background: The consumption of cold brew is relatively new, and guidelines with conditions and parameters to produce cold brew are still lacking. In this study, the parameters to obtain cold brew coffee from Coffea arabica were optimized to obtain a coffee extract rich in caffeine and soluble solids. The effects of extraction time, particle size of ground coffee, extraction temperature, coffee‐to‐water ratio, stirring on caffeine yield, and soluble solids on caffeine concentrations were studied. Results: Optimized parameters showed 45 min sufficed to perform a cold extraction at 4°C and 24°C. The parameters selected for validation were 24°C, 30% coffee‐to‐water ratio, a stirring of 400 rpm resulting in 3.98 mg/ml of extracted caffeine, 11.20 °Brix, and 93.9% of caffeine yield. The smaller particle size (595 μm) displayed the higher caffeine extraction of about 4 mg/ml. Conclusion: This study reveals the high efficiency of cold brew extraction and its potential at the industrial scale, decreasing costs with energy and extraction time, and producing a coffee rich in caffeine and soluble solids. [ABSTRACT FROM AUTHOR]