Reduce food industry fouling

US researchers claim to have developed a way to modify stainless steel surfaces that dramatically reduces fouling during food processing and improves efficiency.

Fouling is a common problem on surfaces that come into contact with food, such as heat exchangers and conveyors. This can lead to biofilm development, reduced heat transfer and a loss of product quality. Jeffrey Barish and Julie Goddard from the University of Massachusetts, US, say their technique can reduce fouling from proteins and minerals by 97%.

Barish and Goddard used an electroless nickel-plating process to co-deposit nanoparticles of a fluorinated polymer, polytetrafluoroethylene, onto the surface of heat exchanger plates. The modified heat exchanger plates were then used in an 8h process to pasteurise raw milk. The processing run was repeated a further nine times to test the robustness of the coating.

After 10 runs, the researchers found around 0.5mg/cm2 of fouling had built up on treated plates, compared with 13 mg/cm2 on the untreated plates.

The surface coating has a lower surface energy than untreated steel, and is much smoother, which helps to prevent build-up. According to the researchers, the coating process used can be easily scaled up.

The findings were published in Food and Bioproducts Processing, the official research journal of the European Federation of Chemical Engineering (EFCE).

Contact: EFCE