Food Safety Lessons in Clostridium Botulinum

The Food Standards Agency recently issued a Food Alert regarding Jars of Olives which have been distributed to a couple of delicatessens within the London area.

Allegedly 1 person became ill with botulism poisoning after consuming a jar of these olives.

These jars of olives have now been recalled.

The unusual fact about this case is that botulism poisoning is very very rare. The writer can only remember only 2 cases of botulism poisoning, one which occurred last year and originated from France.  Generally speaking food poisoning outbreaks can be attributed to after nasty pathogens such as salmonella, listeria and e coli.

Although Botulism poisoning is very very rare it however can be very very deadly.  Every and each  case of botulism is considered a public health emergency because it is so deadly.

The toxins caused by botulism can attack nervous system and typical symptoms can be blurred vision, difficulty swallowing, difficulty speaking which rapidly get worse. If not treated there is a high probability of death.

Clostridium Botulinum is an anaerobic bacteria which means that it does not need oxygen to grow which means that ideal medium would be a can or a jar where there is no oxygen. The bacteria is gram positive and spore forming. The spores are heat resistant and can survive in foods which have been incorrectly or minimally heat processed. The toxin can be destroyed if heat processed at 80*C for 10 minutes or longer. (NOTE: to destroy salmonella the heat process is 70*C for 2 minutes or longer).

Almost any type of food that is not very acidic (pH above 4.6) can support growth and toxin production by C. botulinum.

Lets looks at these jars of olives!!!

They would be a non oxygen environment ideal for C. botulinum.  C. botulinum generally is usually found in the soil so Olives would not have been considered a significant risk from C. botulinum. 

However if they contained some herbs then this would have increased the risk. Also the medium would not be acidic enough to destroy the C. botulinum and if they had not been heat treated to the correct temperature/time then this would be an ideal environment for the toxins to grow and flourish.

Food Safety is essential and if we don’t get it right or DON’T UNDERSTAND THE RISKS the consequences can be huge.


About ABurne

Andy Burne has worked in Technical Management for many years in the food industry. Now he is a certified BRC auditor and provides consultancy to the Food Industry.