Emerging technologies for the recovery of isothiocyanates, protein and phenolic compounds from rapeseed and rapeseed press-cake: Effect of high voltage electrical discharges

The aim of the present research study was to gain insight into the applicability of high voltage electrical discharges (HVED) technology for obtaining high-added value compounds (protein, polyphenols and isothiocyanates) from rapeseeds and rapeseed press-cake. For this purpose, HVED treatment was applied at different energy inputs (0-400 kJ/kg) to raw rapeseed and rapeseed press-cake water suspensions at different liquid-to-solid ratios (1:5-1:20, w/w). The obtained results clearly show the high potential of HVED to recover isothiocyanates, phenolic compounds and proteins which can be used as food additives and/or nutraceuticals. In almost all cases, an optimal treatment energy input (80 kJ/kg or 240 kJ/kg) was observed beyond which the content of the biocompounds decreases. This optimal energy input was changing depending on the considered compounds and on the raw materials. For example, for polyphenols, the optimal energy was 80 kJ/kg with rapeseed press-cake, but it was 240 kJ/kg with rapeseeds. (C) 2015 Elsevier Ltd. All rights reserved.