Proposal for the Use of an Industrial Membrane System for Lactose Recovery From Whey: Adaptation of Technology Used...

This study evaluated the feasibility of recovering and concentrating lactose from ultrafiltration (UF) permeate of sweet whey using nanofiltration (NF) and reverse osmosis (RO) under industrial conditions. The objective was to adapt existing whey protein recovery systems to valorize the lactose fraction. UF permeates from different batches were concentrated by NF at 16-25 bar, with 16 bar combined with diafiltration showing the best performance for lactose concentration. The NF concentrate was further concentrated by RO, increasing lactose content and reducing mineral levels. Spray drying produced a powder containing 94.10% lactose, with low moisture (0.98%), low water activity (0.258), and moderate hygroscopicity (5.20%). FTIR and physicochemical analyses confirmed lactose purity, and the overall process yield reached 87.68%. The integration of NF, RO, and drying proved technically efficient for lactose valorization and demonstrated that membrane systems traditionally used for protein recovery can be adapted for industrial lactose production, contributing to the added value of whey. A complete mass balance and environmental assessment would further strengthen the evaluation of its economic and environmental performance. PRACTICAL APPLICATIONS: This research demonstrates the feasibility of converting cheese whey, a commonly discarded dairy byproduct, into high-purity lactose using industrial membrane technologies. The proposed process achieved good yield and operational efficiency by adapting existing systems already used in the dairy industry. This approach supports the valorization of whey, reducing environmental impact while generating a high-value ingredient. The recovered lactose has wide applicability, including use in the food industry, pharmaceuticals, cosmetics, and potential bioenergy applications. Overall, the study contributes to improving sustainability and value generation within the dairy production chain.