New nano coatings being introduced by INM, the Leibniz Institute for New Materials, Germany, will be a boon to the food industry.

The nano coatings it has developed reduce microbes and persistent biofilms on heat exchangers, thereby requiring the exchangers to be intensively cleaned far less often.

The innovation will help maintain high standards of hygiene during milk and juice processing. High standards call for keeping the number of microbes at a minimum during the whole process so that there is no risk to the consumer. Heat exchangers are used in numerous steps throughout the process. In spite of the fact that the large surface in the heat exchangers cools down the heated, liquid foodstuffs again quickly, microbes can remain stuck in the numerous grooves and recesses of the heat exchanger, causing persistent biofilms to be formed or sticky residues to accumulate. As a result, heat exchangers must be cleaned at regular intervals using aggressive chemicals. 

The new nano coatings reduce the effort required for cleaning heat exchangers. In these new coatings, the research scientists combine antiadhesive and antimicrobial qualities.

Colloidal copper is used in the coatings which yields copper ions on account of the presence of oxygen or water present in many foodstuff processes. These ions travel to the surface and their antimicrobial effect prevents microbes from settling there. The anti-adhesive characteristics are achieved by introducing hydrophobic compounds that are similar to common teflon. These prohibit the formation of any undesired biofilm and allow residues to be transported out more easily before they clog up the channels of the heat exchangers.