Consecutive high-pressure and enzyme assisted fractionation of blackberry (Rubus fruticosus L.) pomace into functional ingredients: Process optimization and product characterization.

In this study supercritical carbon dioxide (SFE-CO2) and pressurized liquid (PLE) extractions were optimized for the recovery of valuable fractions from blackberry pomace. Consecutively applied SFE-CO2 and PLE at optimized parameters yielded 9.9, 26.3 and 5.1 g/100 g of CO2, ethanol (EtOH) and water-soluble extracts, respectively. Oil of lipophilic fraction was composed mainly of healthy polyunsaturated fatty acids (linoleic 64.1%, α-linolenic 12.9%), while polar solvents effectively recovered antioxidants (up to 29.1 mg gallic acid and 168.7 mg Trolox equivalents from g pomace). PLE-EtOH extract contained 12.2 mg/g of cyanidin-3-glucoside, while other anthocyanins were detected in significantly lower quantities (0.5-0.7 mg/g). SFE-CO2 and PLE reduced the antioxidant capacity of starting plant material by 86-93%. In terms of extraction time, solvent consumption, total yields, and phytochemical characteristics, high-pressure fractionation was more efficient for obtaining valuable pomace constituents as compared to conventional and enzyme-assisted extractions.