Titanium could fight food poisoning
Titanium could help the food industry slash the number of food poisoning cases in the UK every year, scientists heard yesterday.
Speaking at the Society for General Microbiology's Autumn meeting being held this week at Trinity College, Dublin, researchers from Manchester Metropolitan University said that food factory surfaces coated in titanium could be easier to keep free of bacteria than more tradition stainless steel surfaces.
The scientists have looked at the way that different surfaces harbour bacteria that could contaminate food and found that some pathogenic bacteria found it more difficult to attach themselves to titanium. Researcher Adele Packer said: "It is important that surfaces in a hygienic environment are kept clean. Scratches may entrap micro-organisms such as Escherichia coli and protect them from being removed during cleaning.
"We measured scratches found on different surfaces and reproduced them in our lab. We coated the surfaces with titanium so that they all had the same chemistry and the only difference was the surface roughness."
"Our findings indicate that titanium coating may have a role in reducing the attachment of E. coli to food contact surfaces; E. coli cells attached to stainless steel much better than titanium."
The researchers found that the shape of bacteria affected their retention: rod-shaped Listeria remained in tiny scratches less than 0.5 micrometers across, and round Staphylococcus cells stuck in scratches measuring 1 micrometer across.
"The results show that surface scratches retain bacteria well if they are of comparable size. The more tightly the bacteria fit in the scratches, the more difficult they are to remove during cleaning," said Packer.
Delegates at the conference also heard that standard ultraviolet (UV) light and detection techniques might not show up the minute quantities of food soil that are stuck to surfaces, making it difficult to decide on the best way to clean them.
Researchers from Manchester Metropolitan University compared different methods used for the detection of food industries and found that using more complex analytical methods is the most effective way to identify the food soil and develop a suitable cleaning regime.
"Some methods are not as sensitive as others at detecting food residue and micro-organisms in the food industries. A rapid industrial technique using UV light may be optimised to detect soil," says Dr Kathryn Whitehead. "Our results also showed that different techniques may be better suited to different disciplines."