Salmonella and E. coli bacteria found in packets of shelled nuts

1 July 2009

Consumption of nuts has gone up, reflecting a growing preference for snacks that are both healthy and convenient. The study was therefore undertaken to explore the microbiological safety of a selection of these products including brazil nuts, cashews and peanuts.

Between October 2008 and March 2009, councils collected 2,866 samples of nuts of different varieties from randomly selected retail premises such as supermarkets and health food shops. Testing of the nuts showed that at least 99% were of a satisfactory or acceptable quality in microbiological terms. However 0.1% of samples were found to be unsafe due to the presence of Salmonella, which is unacceptable in ready-to-eat foods. E. coli, the presence of which indicates poor hygiene was found in a total of 0.8% of the samples; and in 0.03% of samples the level of E. coli was assessed as being too high and therefore unsatisfactory in microbiological terms.

Dr Jim McLauchlin, Director of the Health Protection Agency's Food, Water & Environmental Microbiology Services, said:

"Our study shows that the vast majority of ready-to-eat nuts tested were safe to eat; however, a very small number were contaminated with unacceptable levels of Salmonella. Ready-to-eat foods contaminated with even low levels of Salmonella can cause illness. The Food Standards Agency was immediately informed of affected batches; these were recalled and full investigations undertaken."

LACORS Chairman, Councillor Geoffrey Theobald OBE, said:

"Councils across the country are supporting businesses to help ensure that the food we eat is safe. Studies like this are a powerful means of councils working together to protect their communities by responding to emerging trends and potential risks.

The full report can be found on the Health Protection Agency's website at the following link: http://www.hpa.org.uk/foodsampling

ENDS

Notes to editors:

1. Samples of nuts of different varieties were collected from randomly selected retail premises from lists held by Local Authority Environmental Health Departments (EHDs).
2. Samples tested were either of a single type of nut or of 'mixes' with a combination of  two or more of the single types. Single types of nuts sampled were almonds, brazils, cashews, hazels, macadamia, peanuts, pecans, pine nuts, pistachios, walnuts and other nuts (chestnuts and soya nuts).
3. Most of the nuts sampled were whole, though some were halved/broken.  
4. Of the single types of nuts sampled, Brazils were the most contaminated nut - 0.4% of samples were contaminated by Salmonella and 2.1% were contaminated by E. coli.
5. Nuts sampled in this study were imported into the UK from over 30 countries.

Media enquiries: Tycie West - 020 7759 2834/ tycie.west@hpa.org.uk

Last reviewed: 1 July 2009