Optimization of microwave-assisted extraction based on absorbed microwave power and energy

The intrinsic microwave power and energy required for optimizing MAE was investigated for the extraction of active compounds from cocoa (Theobroma cacao L.) leaves at various extraction scales. To carry out this investigation, an optimization method based on absorbed power density (APD) and absorbed energy density (AED) were developed based on the extraction mechanism of MAE using sequential single factor experiments. The optimized results are consistent with those obtained by the conventional optimization method using response surface methodology (RSM) and also comparable with that of the optimized Soxhlet extraction. The main advantage of the method is that the intensive optimum conditions obtained at solvent to feed (S/F) ratio of 50 ml/g, APD of 0.3 W/ml and AED of 300 J/ml are capable of determining the specific optimum operating conditions (S/F ratio, power, time) of the MAE at various scales of 100-300 ml with great accuracy.