OPTIMIZATION OF MICROWAVE-ASSISTED DRYING OF JERUSALEM ARTICHOKES (HELIANTHUS TUBEROSUS L.) BY RESPONSE SURFACE METHODOLOGY AND GENETIC ALGORITHM

The objective of the present study was to investigate microwave-assisted drying of Jerusalem artichoke tubers to determine the effects of the processing conditions. Drying time (DT) and effective moisture diffusivity (EMD) were determined to evaluate the drying process in terms of dehydration performance, whereas the rehydration ratio (RhR) was considered as a significant quality index. A pretreatment of soaking in a NaCl solution was applied before all trials. The output power of the microwave oven, slice thickness and NaCl concentration of the pretreatment solution were the three investigated parameters. The drying process was accelerated by altering the conditions while obtaining a higher quality product. For optimization of the drying process, response surface methodology (RSM) and genetic algorithms (GA) were used. Model adequacy was evaluated for each corresponding mathematical expression developed for interested responses by RSM. The residual of the model obtained by GA was compared to that of the RSM model. The GA was successful in high-performance prediction and produced results similar to those of RSM. The analysis and results of the present study show that both RSM and GA models can be used in cohesion to gain insight into the bioprocessing system.