Pine nuts are a popular addition to salads, and are also a crucial ingredient in pesto sauce. Reports of an unpleasant taste following consumption of pine nuts circulated in Belgium in 2001, prompting the Poisons Centre to conduct a comparison of affected and unaffected nut batches. Although they concluded there was no safety threat, no chemical differences were found.
In recent months, however, the problem has arisen again, not only in the UK but in other parts of the world, too. Incidents in the US are said to have followed consumption of nuts imported from China. In the UK the problem has led a number of consumers to contact the food regulator for an explanation.
The unexplained phenomenon could have an impact on ingredient sourcing and screening by food manufacturers – although it is unlikely that they will be able to take measures to ensure product quality is not affected until the underlying reason is found.
The FSA has now confirmed that it is taking on the matter – although it emphasised that it is not a food safety issue. “As far as the Agency is aware, no adverse health effects have been associated with these symptoms.”
It expects the task to be tricky given the lack of information available, but is inviting people who have experienced the problem to email toxicology@foodstandards.gsi.gov.uk with details of the pine nuts consumed and how long they had the metallic taste for.
Not everyone
Even more curiously, the metallic taste is reported to affect only some people who have eaten nuts from an affected batch, and not others.
Clinical director of the charity Allergy UK John Collard, said it is unlikely to be down to allergy, according to a Daily Mail report. He suggested that some of the oils in the nuts may have become rancid due to poor storage, and that some people are more susceptible than others.
Got a hypothesis?
FoodNavigator would be interested to hear from anyone in the food industry with a theory about what could be causing the problem.
You can share your thoughts by emailing jess.halliday ‘at’ decisionnews.com.
Please write ‘Pine mouth’ in the subject line; all comments will be taken as ‘on the record’ and may be published along with the sender’s name and affiliation.