Allergen levels: how low is low?
This is a question where the food industry would prefer some guidance in order to minimise the use of precautionary labels such that they are only used to protect sensitive consumers from levels which would otherwise trigger a problem. This month the Food Standards Agency announced that it had started a sampling and testing programme at 13 milling plants across the UK to investigate the presence of soya in wheat flour. It follows recent reports that wheat flour may contain soya. In a previous study by the National Association of British and Irish Millers in 2013 low levels were found. Based on evidence they have received to date the FSA believes that the levels of soya present are unlikely to pose a risk to people with a soya allergy and do not need precautionary labelling. The new testing programme is to verify this risk assessment and also the accuracy of information supplied to consumers on flour and flour based products. EFSA has been asked to deliver an evaluation of allergenic ingredients and is currently reviewing comments following a period of consultation before delivering a scientific opinion. Meanwhile food producers can refer to the allergen risk assessment tool, VITAL 2.0, and a reference dose that is based on an eliciting dose of an allergen at which a proportion of the allergic population would be likely to react, but does not identify a dose below which no allergic individual would react. In the case of soya when the reference dose is 1mg soya protein, this would equate to a level of 20ppm soya protein in a 50g portion. Detecting such levels of adventitious contamination should be possible with current ELISA methods, depending on the source and nature of the contaminant. For example, the Soya-Check ELISA will quantify soya flour at levels between 2 and 25ppm or 0.9 to 10ppm soya protein. The results between different ELISAs can be different – for example due to the lack of reference materials used to assist calibration. Such analytical issues will need to be addressed before allergen thresholds can be introduced in order to ensure precise and accurate analytical results support the consistency required with such an approach to precautionary labelling.