Scientists tackle bacteria on processing surfaces

Food producers can reduce time and energy spent on cleaning by using machines with modified surfaces. Product is less likely to get stuck in production lines.  

The conference is organized by chemical engineering departments at the universities of Cambridge and Bath. Dr Ian Wilson, congress secretary, told FoodQualityNews.com a number of papers on modified surfaces will be presented.

Harbor for micro-organisms​

“People ask how we can modify surfaces to stop things sticking to them. We’ve got the companies making the surfaces, and scientists looking at whether they’re effective or not,​” he said.

Unwanted layers of product get left behind on equipment during food processing, known as fouling or coating.

“Whenever you heat up milk in a pan, you always have a creamy white layer left. It’s an unwanted layer,​” said Wilson.

“In many aspects of food processing, material gets left behind on the processing surface. A considerable amount of time and effort and money is spent on cleaning these units.​

“It also has quite serious microbiological aspects because these layers are harbors for many types of micro-organisms.​”

Environmental impact​

Most production lines use water-based techniques for cleaning. The need to reduce water consumption, energy use and impact of chemicals is increasingly important to the industry.

“If you think about washing up in the kitchen, all the product you buy goes down the drain,​” said Wilson.

“The environmental impact of cleaning operations is enormous. The idea of green cleaning is improving the performance of the unit and efficiency of the cleaning operation to maximize productivity, and minimize environmental impact.​”

Modified surfaces can reduce the build-up of product, meaning less time is needed for cleaning. Downtime is decreased, and productivity is increased. Savings are made on energy and water costs.

Wilson says there is not a ‘one-size-fits-all’ surface. Both the material and the food product must be taken into account. “The stickiness of different foods differs,” he said. “What is sticky for one is not sticky for another. It’s all to do with the surface chemistry.​”

The conference’s provisional programme includes papers on antibacterial stainless steel surfaces via surface modification; the effect of surface properties on the removal of bacillus cereus​ and pseudomonas fluorescens; ​and the use of photocatalytic surfaces in the brewing industry.

Other topics include Fouling, Cleaning, the Fluid Mechanics of Cleaning, and Membranes.

The conference is on March 31 – April 2 at Jesus College Cambridge. It is open to academics and industry professionals.