Pulsed electric field combined with microwave-assisted extraction of pectin polysaccharide from jackfruit waste

Abstract

The present methodology uses the combination of pulsed electric fields (PEF) and microwave-assisted extraction (MAE) of pectin from the jackfruit wastes. Two optimization tools such as Box-Behnken design (BBD) and artificial neural network (ANN) were used to study the extraction yields. The optimized operating conditions obtained after desirability analysis were PEF strength (11.99 kV/cm), PEF treatment time (5.47 min), followed by MAE at power density (647.30 W/g) and time of exposure (5.00 min). From the optimization results, the R2 values of BBD ranged from 0.89 to 0.98 as well as the SSE (sum of squared error) values varied across 0.076 to 0.781 whereas R2 values of ANN fluctuated around 0.95 to 0.99 and MSE (mean squared error) values varied from 0.008 to 0.1. It was observed the ANN was found to be more superior in execution than the BBD model. The extracted pectin was analyzed for structural and functional properties with the comparison to conventionally extracted pectin. The degree of esterification and methoxyl percentage of PEF and MAE pectin was less than the conventionally extracted pectin. The experimental and predicted values were similar for the pectin yield (%), but a higher prediction rate was observed in ANN modelling than BBD. Scanning Electron Micrographs showed an increased rupture and severing of parenchymal cells attributing to enhance extraction yields. Therefore, it can be concluded that the pulsed electric field treatment followed by microwave-assisted extraction resulted in higher pectin extraction with enhanced functional properties than the conventional method.