Chokeberry pomace valorization into food ingredients by enzyme-assisted extraction: Process optimization and product characterization

Abstract

Currently berry juice pressing residues are used inefficiently due to a lack of innovative processes of their valorization. This study reports valorization of chokeberry pomace via combined high pressure fractionation and enzyme-assisted extraction (EAE), utilizing commercially available cellulolytic and xylanolytic enzyme preparations, namely Viscozyme L and CeluStar XL. The results obtained indicate that optimized enzyme treatment (E/S 6% v/w, 40°C, pH 3.5, 7h), especially using Viscozyme L, facilitates pomace cell-wall breakdown and: (1) increases the yield of water-soluble fraction by 44–113%, monosaccharide content by 12–140%, total phenolic content by 29–41%, radical scavenging capacity by 20–39%; (2) promotes some alterations in phenolic acid and flavonol profiles of EAE-derived supernatants. For the first time antioxidant potential of solid residues from enzyme-treated berry pomaces was evaluated too, indicating that all fractions could be utilized as a low-cost source of high added value functional ingredients with various scientific and commercial applications.