Feasibility of water-to-ethanol solvent exchange combined with supercritical CO2 drying to turn pea waste into food powders with target technological and sensory properties
Lara Manzocco, Lorenzo Barozzi, Stella Plazzotta, Yanjun Sun, Song Miao, Sonia Calligaris
Abstract
Ethanol solvent exchange combined with supercritical–CO2–drying (SE + SCD), was applied to upcycle substandard peas generated by industrial processing into food powders with target technological and sensory properties. Control powders were produced by traditional air- (AD) and freeze- (FD) drying. SE + SCD promoted carbohydrate and lipid leaching, resulting in a pea powder with protein (32 g/100 g) and fiber content (30 g/100 g) higher than that of AD and FD powders. SE + SCD also caused conformational changes in hemicellulose and partial protein denaturation, as detected by FTIR. Compared to AD and FD powders, SE + SCD one was colourless and more porous, as indicated by the low density (0.16 g cm−3) and SEM microstructure. The open-pore structure of SE + SCD powder also accounted for higher water (5.2 g water/g powder) and oil (4.7 g oil/g powder) holding capability. Sensory analysis revealed that SE + SCD produced a flavourless powder, with no vegetable sensory notes.