In Brief

Abstract

Recently, membrane separation techniques are extensively used in a dairy industry, which contains many valuable substances (proteins, lactose, minerals) which can be further used, e.g. in food industry or biotechnologies. This paper summarises a potential of membrane separation process, namely ultrafiltration and nanofiltration, in fractionation of whey components, such as proteins and lactose. It also brings data from desalination of lactose from natural salty whey (from various Czech dairies). Whey was treated by pilot-plant ultrafiltration (Bollene, France) on tubular ceramic membranes (Membralox, Pall) and obtained permeates were purified by nanofiltration spiral wound membranes. We compared two different commercial nanofiltration membranes NTR-7450-S2F (Nitto Denko) and FILMTEC NF270-2540 (Dow) under various conditions. Permeate flow rates on the 500 nm ultrafiltration membrane achieved 6.9 – 44.5 L/h.m2.bar and mass concentration factors were 1.2 – 16.5. This value suggests potential industrial application. Lactose apparent rejections on NTR-7450-S2F were in a range of 82 – 98% and slightly lower (82 – 90%) on the FILMTEC NF270-2540 membrane. Rejections of ions were comparable for both membranes. All experiments confirmed severe membrane fouling on both membranes.