ANTI-FOULING STAINLESS STEEL BASED SURFACES FOR MILK HEATING PROCESSES

Abstract

One of the strategies which have been defended to reduce fouling during heat treatment in the dairy industry is to modify the surface properties of the stainless steel used in heat exchangers, in order to decrease its appetence for milk deposits. Previous studies performed in our laboratory on fouling caused by milk components on several stainless steel materials with different surface modification techniques showed the importance of specific surface properties on the type of deposit formed. One of those properties was the surface energy. In the present study, several surfaces with specific surface energies and similar surface composition were obtained by one of the most promising modification technique tested before, reactive sputtering, and were used as fouling supports in contact with a milk simulating solution under constant conditions of temperature, pH, calcium concentration and hydrodynamics. The aim of these new experiments was to quantify deposition and removal parameters, based on the influence of surface energy on the type of deposit formed. A new dependence relation between the amount of deposit formed and the remaining deposit after cleaning with water and the surface energy of the surface, more precisely its �