Recovery of bioactive compounds from agro-food wastes by membrane-based operations

With a market volume of 800-850 million of Euro/year, the food industry represents the second biggest worldwide industrial market for membranes after water and wastewater treatment with a growth of around 7.5% per year. Main applications concern the dairy industry (i.e. whey protein concentration, milk protein standardization, etc.) followed by beverages (wine, beer, fruit juices, etc.) and egg products. The combination of conventional and membrane separation technologies offers a wide range of advantages in the agro-food productions in terms of improvement of the product quality, energy saving and reduction of water consumption and environment impact. Selected applications of membrane unit operations and integrated membrane systems in specific areas of the agro-food production (artichoke, citrus and olive oil production) are reviewed and discussed, highlighting their potential with respect to the separation, concentration and purification of high-added value compounds from aqueous exhausted solutions. Integrated membrane processes are proposed in order to rationalize the productive cycle according with a zero discharge strategy through the recovery of bioactive compounds and the reuse of water and specific fractions obtained in the fractionation process.