The bacterium is one of the major causes of botulism, which is a rare but deadly form of food poisoning. Botulinum neurotoxin is an extremely potent toxin as just 30ng is sufficient to cause illness and even death, and the presence of just 0.01g of C. botulinum in food can result in botulism.
In their research, the IFR and the Nestle Research Centre focused on non-proteolytic C. botulinum as opposed to the proteolytic form.
This is because non-proteolytic C. botulinum is able to grow and produce toxin at temperatures as low as 3oC whereas proteolytic C. botulinum will only grow above 12oC. Non-proteolytic C. botulinum is therefore considered a major health hazard in minimally heated refrigerated foods, such as chilled ready meals.
The IFR claims that the method it developed with the Nestle Research Centre will help provide food companies with high quality information on the incidence of the spores in such food products.
The institute of the Biotechnology and Biological Sciences Research Council (BBSRC) said that unlike some previous techniques, the new method is specific, and enumerates only non-proteolytic C. botulinum spores. It claimed that the method which uses an enrichment procedure designed specifically to grow non-proteolytic spores in food sample is also very sensitive, with a low detection level.
The method is designed to provide the data the food industry needs for quantitative microbial risk analysis. This allows the total risk from spores of non-proteolytic C. botulinum to be calculated so that appropriate risk management options can be taken.
Professor Mike Peck, head bacterial foodborne pathogens at IFR, told FoodProductionDaily.com that large food companies with their own container facilities can use the method in-house while smaller companies may have to send samples away.
Funding for the research was provided by the Nestle Research Centre.
Source: Appl. Environ. Microbiol. 76, 6607-6614
Development and application of a new method for specific enumeration of spores of nonproteolytic Clostridium botulinum types B, E and F in foods and food materials
Authors: Peck, M.W. et al