16 November 2023
Food allergies affects a significant proportion of the population, with around 1-2% of adults in the UK suffering with the condition. Someone with a food allergy will experience an inappropriate immune response if they are exposed to the protein of the food that they are allergic to. In some cases, these reactions can be severe, and in the worst cases, fatal.
Lots of research and VITAL testing continues to be conducted around the world, to help us understand why people develop allergies, and to measure the smallest amounts of protein that can trigger an allergic reaction in an individual.
This global data is collated and used to help us understand the lowest levels of protein (for each allergen) that are likely to elicit an allergic reaction in some of the most sensitive people. These established protein levels are referred to as ‘reference doses’.
One key aim of all this work is to help the food industry to progress towards ‘action levels’. The term refers to the level of allergen protein at which action should be taken in the form of applying a precautionary label. Understanding these levels should promote consistency in the approach to using Precautionary Allergen Labelling (PAL) across the industry.
The VITAL program was developed by the Allergen Bureau in Australia and New Zealand and was designed as a tool to help businesses to decide whether PAL was appropriate (VITAL stands for Voluntary Incidental Trace Allergen Labelling). The tool uses VITAL test data relating to the user’s products and ingredients, and any levels of unintentional allergen protein they contain, to calculate whether these would equate to levels at or above the reference doses for those allergens. It is recommended that PAL is applied to the product if the recorded levels are at or above the VITAL test reference dose.
The reference doses used in the Allergen Bureau’s VITAL program are the doses of allergen at which 1% of the allergic population are likely to start to have a reaction and are reported as the ED01 levels (ED meaning Eliciting Dose and 01 meaning 1%). As these reference doses were published linked with the program, they became known as the VITAL reference doses.
If a business is adopting the VITAL approach and is using these reference doses to make decisions about whether to apply precautionary labelling, it is critical that the right sampling and VITAL testing approach is adopted. Sampling needs to be based on risk, and represent the worst-case scenario in order to capture the highest levels of contamination. The VITAL testing undertaken needs to be based on the detection of protein, so typically ELISA is the method of choice. Working with a laboratory that understands how reference doses can be applied will also be beneficial when it comes to interpreting the VITAL test results.
Many businesses have attempted to adopt the VITAL approach and perform calculations intended to assess contamination levels, only to discover that it is not as simple as it first appears. Many considerations are needed, including the source of the contamination, portion sizing, the proportion of contaminated ingredients, and the interpretation of analytical testing results.