CHAPTER 13: The Almond and Mahaleb Allergen Story – PCR Resolution of Live Incident Investigations

Food allergies represent a threat to the health and well-being of those affected. Food producers must provide food that is safe and properly labelled and government is under pressure to maintain a regulatory framework that both protects consumers and facilitates responsible businesses. During 2014–2015, a number of spice products were recalled from the international market due to the suspected unlabelled presence of almond, a known allergen. Initial conventional testing approaches indicated the presence of almond but further analyses appeared to contradict the initial results, indicating the presence of a similar but unknown compound. DNA polymerase chain reaction (PCR) investigations featured prominently in the multidisciplinary approach of the Government Chemist team called in to resolve the issue. It was conclusively demonstrated that contamination in a sample of cumin was due to mahaleb, rather than almond. Following confirmation that almond was not present in the cumin, the food recall was rescinded. Another batch of spice, this time paprika, tested positive for almond and was prevented from entering the UK supply chain. Further investigation by the Government Chemist team confirmed that almond was indeed present. The lessons learned from these investigations led to a novel published strategy to deal with incidents like this and a seminar was organised to provide face to face knowledge transfer to official control and trade laboratories.