Reducing Milk Protein Adhesion Rates: A Transient Surface Treatment of Stainless Steel

Abstract

The primary factor in developing a surface that diminishes fouling during food processing is reducing the rate of formation of the initial foulant layer. Modifying the properties of plant processing surfaces, which are typically 316 L or 304 L stainless steel, is one way of achieving a reduction in initial adhesion rate. We have developed a transient treatment that modifies the surface properties of the metal oxide surface, that is shown to reduce the interaction potential between the stainless steel processing surface and phosphate anions. The phosphate anions are involved in the conditioning layer associated with foulant formation during milk processing. The transient nature of the treatment is that it is present during the processing cycle, but is removed at high pH, which is an environment that exists during the cleaning cycle. The transient surface treatment was utilized in fouling trials, conducted in a pilot plant milk pasteurizer, a model system to emulate milk fouling in industrial plant. Evaluation of the result shows significant reductions in fouling rates compared to the typical controls, as indicated by the pressure drop across the plate heat exchanger and the observed reduction in the fouling of the heat exchanger plate.