Integrated Flash Vacuum-Expansion and Cryostructuring for Resource-Efficient Tamarillo Biomass Processing

Tamarillo (Solanum betaceum) processing is characterized by early biomass exclusion and thermal stabilization, which may limit in-process retention of phytochemicals. This study evaluated an integrated sequence combining Flash Vacuum Expansion (FVE) under different processing conditions with whey protein-based cryostructuring as a strategy to enhance the redistribution and structural immobilization of tamarillo bioactives. FVE promoted migration of phenolics and pigments prior to mechanical fractionation. Selected FVE-treated puree was incorporated into a whey protein matrix and subjected to cryostructuring and freeze-drying to generate a porous stabilization scaffold. Structural characterization by scanning electron microscopy and gas adsorption confirmed the formation of an interconnected porous matrix. Cryostructuring reduced water activity to 0.17 ± 0.01 and produced high porosity (91.9%) with low bulk density (0.109 g·cm−3). Total phenolic retention exceeded 83%, while anthocyanins showed greater sensitivity (46% retention). No statistically significant additional losses of phenolics or antioxidant activity were observed during cryostructuring relative to gelation. The integrated approach illustrates a process-level stabilization pathway in which redistributed phytochemicals are physically confined within a porous scaffold, providing a structurally differentiated alternative to conventional drying for improved in-stream resource utilization.