BETA-LACTOGLOBULIN FOULING AND ITS REMOVAL UPON RINSING AND BY SDS ASINFLUENCED BY SURFACE CHARACTERISTICS, TEMPERATURE AND ADSORPTION TIME

The extensive fouling common in the food industry puts high demands on equipment cleaning. The adsorption of beta-lactoglobulin and its remo val by the anionic surfactant sodium dodecyl sulphate (SDS) were follo wed at pH 6.0 using in situ ellipsometry. Hydrophilic chromium oxide a nd stainless steel together with hydrophobic methylated silica were st udied at different temperatures. Differences between chromium oxide an d steel were small, while hydrophobic silica showed significantly diff erent initial adsorption kinetics and adsorbed amounts. Also, the temp erature-dependence of the amount desorbed upon rinsing as well as of t he overall cleanability differed greatly. At around the beta-lactoglob ulin denaturation temperature, multilayer build-up at the surface was seen, and the cleanability was very low. Of two protein adsorption tim es employed, the longer resulted, for metal oxide surfaces, in less de sorption during rinsing. Copyright (C) 1996 Elsevier Science Limited