Abstract
Ultrafiltration (UF) is one of the membrane processes which is mostly used in the dairy industry for the separation and concentration of whey components or fermentation broth. Fouling of UF membranes in the food industry is primarily due to a deposition of microorganisms, proteins, fats and minerals on the membrane surface. Thus, cleaning of the membranes is an essential step of UF separation. The results from investigations of chemical cleaning of a ceramic UF membrane fouled by precipitation of whey components and yeast contained in the fermentation broth are presented. The effect of cleaning procedure on the degree of permeability restoration by the fouled membrane was studied. The results demonstrated that a combination of sodium hydroxide, phosphoric acid and sodium hypochlorite as a disinfectant could be successfully used to achieve an optimum recovery of the membrane properties.