Graphite-based composites for whey protein fouling and bacterial adhesion management
Résumé
Dairy industries are burdened by fouling phenomena that increase costs and environmental impacts of thermal processes. One remedial solution could be to replace stainless-steel equipment by other materials less prone to fouling. This work studied the fouling behaviour and hygienic features of two hydrophobic and non-polar commercial graphite-based composites (Graphilor (R) XC and XTH) that were exposed to isothermal whey protein fouling in an industrial pasteurisation unit and to foodborne pathogenic bacterial strains, namely Staphylococcus aureus, Listeria monocytogenes and Salmonella enterica. Both composites exhibited impressive fouling-release properties: a simple 20 min water rinse was enough to remove all dairy deposit after 1.5 h of pasteurisation, as opposed to usual heavy clean-in-place procedures. The composites also showed a significant effect on bacterial adhesion, exhibiting lower cell counts than stainless-steel surfaces. These results suggest that graphite-based materials might successfully replace stainless steel as equipment material to reduce fouling in dairy fouling industries.