Effect of pulsed electric field on texture and drying time of apple slices.

Abstract

Effect of pulsed electric field (PEF) strength, pulse duration and temperature used during PEF assisted blanching pretreatment on energy input, cell disintegration index and drying time of apple slices was studied. A central composite rotatable design was used for designing the experiment and to visualize the effect of variables on responses. The level of variables used in the design varied from 1 to 2kVcm-1, 25 to 75, and 60 to 80°C for electric field strength, number of pulses and temperature of water during PEF assisted blanching pretreatment, respectively. The variables affected significantly the responses and polynomial quadratic models employed to visualize the effect of variables on different responses were found to fit well with high R2 values (0.84-0.99) indicating fitness of the models in describing the effect of variables on responses. An optimized condition for variables was derived at 1.25kVcm-1, 50, and 80°C for electric field strength, number of pulses temperature during PEF assisted blanching pretreatment, respectively with a desirability value of 0.85. High correlations were recorded between predicted and actual values for responses at optimized conditions of variables and the same can be used for production of dehydrated apple slices with low energy input.