FBOs may voluntarily use labelling such as ‘produced in a kitchen which uses…’ FSA Food Allergen Labelling and Information Requirements: Technical Guidance – June 2020 . In at least three studies now, foods with precautionary labels “did contain” the allergen in question.
For example: Old FDA guidance for the food industry states that food allergen advisory statements, e.g., "may contain [allergen]", "produced in a facility that also uses [allergen]", etc. The EU Food Information for Consumers (EC Regulation No. Some of these are: Myth: “May contain” or similar precautionary statement is required on the label. Many food producers use precautionary allergen labelling (PAL) (e.g. Food Allergen Labelling - PDF (167 kb) If you are selling or making a packaged food that contains any priority food allergens, gluten sources or added sulphites, then your product likely requires allergen labelling.

A large group of world experts in food allergy and immunology, including Katie Allen and Stephen Taylor from the Allergen Bureau VITAL Scientific Expert Panel, have recently published an open access article calling for an international framework to drive global consistency in allergen labelling, particularly precautionary allergen labelling (PAL). Food allergens may also be present due, for example, to shared equipment or use of ingredients containing undisclosed allergen. The aim of introducing allergen thresholds is to limit the use of precautionary allergen labelling (also known as PAL or ‘may contain’ warnings) so that it is only used where a food poses a real risk; while at the same time ensuring that people with food allergies are well-protected. (2014) Allergen Reference Doses for precautionary labeling (VITAL 2.0): clinical implications J Allergy Clin Immunol.

SHARE ‘may contain …..’) to alert consumers to the possible unintended presence of allergens. In these cases, the Allergen Bureau recommends you use the VITAL ® Program to provide meaningful risk-based precautionary labelling. You can choose the method you want to use to emphasise the allergen in the ingredients list. This can be done by listing them in bold or contrasting colours or underlining. Myths about the use of precautionary statements, such as “May contain,” have spread through the industry. I imagine anyway that Precautionary Allergen Labelling guidance is an entirely separate issue — ‘may contain’ versus ‘does contain’. How to label allergens on your food product. See our article Advisory Labels: May Contain Confusion about a 2013 study in which products with “may contain” warnings were tested for the presence of peanut allergen. upon scientific data. Allergen Bureau , summary of the VITAL scientific expert panel recommendations 2011 1169/2011) required this mandatory disclosure to be extended to include non‐ and prepacked foods from December 2014.