Experimental Analysis of the Influence of Inter-Electrode Distance in Juice Extraction Processes Using Pulsed Electric Fields

Abstract

Nowadays, the pulsed electric field (PEF) is widely used in the food industry. The PEF treatment ofdifferent fruits and vegetables before the extraction process has already been used, and its efficiency has alreadybeen proven concerning the increase of the quantity of juice extracted, while keeping the aroma and thenutritional quality of the product. The basic concept is to place food in a treatment chamber with two electrodesand use high electric fields to increase the permeability of these cells, a process known as electroporation. Anexperimental study of beet juice extraction process by pulse electric field has been presented. For this purpose,three static treatment chambers of cylindrical shape with different inter-electrode distances were used. The aimwas to determine the influence of the inter-electrode distance in the PEF extraction processes. The methodologyof experimental designs was used in this work by developing a fractional factorial design where the interelectrode distance d was considered as a factor. The results obtained are satisfactory, since it leads us tovalidated mathematical models. For the same experimental conditions, the treatment chamber with the largestinter-electrode distance gave the best performance in terms of quantity of juice extracted. While the one with thesmallest inter-electrode distance is mainly a considerable energy saving but with a low yield in terms of juicemass.