Ultrafiltration and Reverse Osmosis in the Dairy Industry - An Introduction to Sanitary Considerations

Abstract

The general applicability of ultrafiltration and reverse osmosis in the dairy industry is reviewed. Consideration is given to the problems of hygienic design and operation of membrane systems, particularly from the point of view of cleanability and sanitation. Recent technological advances which may accelerate acceptance of ultrafiltration and reverse osmosis as unit operations in the dairy industry are also discussed. The membrane separation processes, ultrafiltration (UF) and reverse osmosis (RO), have found considerable application in the dairy industry, principally for concentration and fractionation of skim milk and whey (3,8). These operations offer both technological and econ-omic advantages over conventional processing methods, and are now becoming increasingly accepted and used commercially on a world-wide basis (J). The requirement of UF and RO equipment to operate under hygienic conditions has been a continual challenge to both design and process engineers. In this review, the objective is to briefly summarize the principles and applications of UF and RO, and to then consider the design and operation of membrane systems from a sanitary standpoint. In addition, an outline of current developments aimed at advancing the state of the technology will be given.