Many foods produced on an industrial scale in enormous stainless steel machines that can be difficult to clean
Washington: Cooking oil coating prevents bacteria from growing in food processing equipment, a new study has found.
Many foods produced on an industrial scale include raw ingredients mixed together in enormous stainless steel machines that can be difficult to clean. With repeated use, equipment surfaces get minute scratches and grooves, providing bacteria and biofilms with the perfect place to hide.
While surface scratches may appear small to the naked eye, they are like a canyon to bacteria, which are only a few micrometres in size. This increases the risk of contamination from microorganisms such as Salmonella, Listeria and E. coli.
Professor Ben Hatton of the University of Toronto's Department of Materials Science & Engineering, Dr. Dalal Asker and Dr. Tarek Awad researched cheaper, safer and more effective ways to prevent bacteria from thriving inside these machines. Their team has proposed a simple new solution: trapping a thin layer of cooking oil at the metal surface to fill in microscopic scrapes, cracks and fissures and create a barrier to bacterial attachment.
They found that this solution resulted in a 1,000x reduction in bacterial levels inside the industrial machines tested. "Coating a stainless steel surface with everyday cooking oil has proven remarkably effective in repelling bacteria. The oil fills in the cracks, creates a hydrophobic layer and acts as a barrier to contaminants on the surface," said Hatton.
Cooking oils such as olive, corn or canola also provide a safer option for cleaning food-processing equipment than the harsh chemicals and disinfectants that are typically used.
The sheer size of the machines makes it harder for cleaning materials to do a thorough job, and leftover bacteria can build up resistance to the cleaning agents. "Contamination in food preparation equipment can impact individual health, cause costly product recalls and can still result after chemical-based cleaning occurs," said Hatton.
The Hatton research group continues to test new combinations of oils, foods and biofilm types to increase the efficiency of the bacteria barriers. They will also explore options of using this method in developing countries to minimize bacterial infection and improve mortality rates.
The full findings are present in the journal- ACS Applied Materials & Interfaces.