Author(s): Brito, Paula S. ; Canacsinh, Hiren ; Mendes, João ; Luis Redondo ; Pereira, Marcos Teotónio
Date: 2012
Persistent ID: http://hdl.handle.net/10400.21/5176
Origin: Repositório Científico do Instituto Politécnico de Lisboa
Subject(s): Bipolar Pulses; Monopolar Pulses; Juice Extraction; Pulsed Electric Fields; Bipolar Pulses; Bipolar Pulses; Monopolar Pulses; Monopolar Pulses; Juice Extraction; Juice Extraction; Pulsed Electric Fields; Pulsed Electric Fields
Additional apple juice extraction with pulsed electric field pretreated apple cubes towards control samples is evaluated. Monopolar and bipolar shaped pulses are compared and their effect is studied with variation of electric field, pulse width and number of pulses. Variation of electric field strength is ranged from 100 V/cm to 1300 V/cm, pulse width from 20 mu s to 300 mu s and number of pulses from 10 to 200, at frequency of 200Hz. Two pulse trains separated by 1 second are applied to all samples. Bipolar pulses showed higher apple juice yields with all studied parameters. Calculation of specific energies consumed was assessed and a threshold where higher energy inputs do not increase juice yield is found for a number of used parameters. Qualitative parameters of total soluble matter (Brix) and absorbance at 390 nm wavelength were determined for each sample and results show that no substantial differences are found for PEF pre-treated and control samples.
