Qualitative characteristics and dead-end ultrafiltration of chicory juice obtained from pulsed electric field treated chicories

Abstract

Qualitative characteristics and dead-end ultrafiltration behavior of chicory juice obtained at different temperatures from untreated and pulsed electric field (PEF) treated chicory roots are investigated. The chicory juices obtained at lower temperatures (30 and 60°C) from PEF treated chicories are less colorized, have lower turbidity, lower protein content, and higher purity than conventional juice obtained at 80°C.The ultrafiltration behavior of the untreated and PEF treated chicory juice was studied in the dead-end filter cell under different pressures (1, 2 and 4bars) and with stirring at 500rpm. Three types of polyethersulfone membranes with MWCO of 150, 50 and 5kDa were used. The membrane with MWCO of 50kDa produced the most purified filtrate, while the membrane with lower MWCO (5kDa) produced less purified filtrate probably due to the partial retention of inulin molecules. The increase of TMP from 1 to 2 bars increased the filtration flux and the juice purity. The ultrafiltration behavior of obtained chicory juices was successfully described by the filtration model with intermediate blocking mechanism.