Leaching and proposed recovery strategies of poly pheno 2025 Trends in Food

Background: Hydration is a critical stage in the processing of canned legumes, yet it often generates a considerable volume of wastewater. Large amounts of bioactive substances, including (poly)phenols and oligosaccharides, leach out into the wastewater, resulting in increased processing costs and compromising the nutritional properties of the canned product. For sustainable production, there is an urgent need to recover these substances. Scope and approach: This manuscript comprehensively reviews the recovery strategies for (poly)phenols and oligosaccharides from legume hydration wastewater. We first explore the potential causes of the loss and leaching of these components into the legume hydration wastewater. The profiles of (poly)phenols and oligosaccharides in the wastewater are outlined. Among the emerging recovery technologies, we selectively focus on the combined use of two techniques: macroporous resin (MR) adsorption/desorption and membrane processes. Key findings and conclusions: Thermal factors are a significant contributor to the losses of bioactive substances. Hydration wastewater generated from each specific legume cultivar exhibits a unique (poly)phenolic profile, including anthocyanins, flavanols, flavonols, tannins, and phenolic acids, and oligosaccharides mostly belonging to the raffinose family. While MR is employed to effectively separate (poly)phenols and oligosaccharides, nanofiltration membranes (150 – 400 Da) are subsequently utilized to purify these components.