Food Safety Focus (23rd Issue, June 2008) – Food Incident Highlight

Clostridium botulinum and Pesto Sauce

In April 2008, there was a recall of a certain brand of pesto sauce in glass jar in the USA. This pasta sauce, which contains basil, mushroom and cheese, was found not acidic enough. As a result it could harbour the bacteria Clostridium botulinum. The toxin the bacteria produced can cause a rare but serious illness called botulism. Symptoms range from vomiting, headache, double vision, to paralysis and in some cases, death.

Clostridium botulinum and its spores only grow in oxygen-free environment but could exist in any low-acid food including herbs and mushrooms. Under favourable conditions, such as when food is stored in jars, tins or oil and without adequate heating, the bacteria begin to grow and produce toxin.

To prevent botulism, never eat canned foods that are dented, leaking or have bulging ends. If homemade foods stored in oil are prepared using fresh ingredients (e.g. vegetables, herbs and spices), they must be kept refrigerated and for no more than 10 days.

Illustration: Pesto sauce