Food allergen quantitative risk assessment: New evaluation of laboratory performance

A recent study published in the peer-reviewed journal Foods by scientists from the EU Commission Joint Research Centre (JRC) highlights the complexities involved in allergen analysis, particularly in extracting allergens from food products. This research focuses on the quantification of total egg and milk protein in cookies, an essential task for ensuring consumer safety and regulatory compliance.  

Allergens can enter food products intentionally or through cross-contact, leading to unintended allergen presence (UAP). While many countries have regulatory frameworks for declaring intentional allergens, guidelines for UAP and precautionary allergen labeling (PAL) are often inconsistent, reducing their effectiveness in protecting allergic consumers. In response, a FAO/WHO expert consultation recommended a priority list of allergenic foods and reference doses (RfDs) to aid in managing UAP, which are critical for consumer safety.  

Accurate allergen quantification is vital for protecting individuals with food allergies. To evaluate laboratory performance, a proficiency test (PT) was organized, involving 20 laboratories that utilized mainly commercial ELISA kits and liquid chromatography–tandem mass spectrometry (LC-MS/MS). The results revealed satisfactory performance for milk protein determination, with 80% of participants demonstrating effective methodologies. However, quantifying egg proteins in heated products proved challenging, as most laboratories reported values significantly below the reference standard, indicating a widespread underestimation of egg protein content.  

Several factors contribute to these differences, including the denaturation of egg proteins during heat treatment, variations in extraction techniques and antibodies used in ELISA kits. The lack of standardized methods and conversion factors for LC-MS/MS analysis further complicates the situation. These challenges underscore the need for regular proficiency tests to assess laboratory performance and adhere to WHO/FAO recommendations.  

The JRC has conducted previous proficiency tests to harmonize allergen measurements across Europe. A 2018 PT focused on cow milk protein in cookies, using a common measurand to allow for the comparison of results across different laboratories. This approach has now been extended to egg and milk protein testing in cookies, with findings expected to enhance laboratory preparedness and method suitability. The results point to a need for improved extraction strategies and the development of antibodies that can better detect heat-treated proteins. 

In conclusion, while many laboratories demonstrated the capability to accurately measure total cow milk protein in cookies, significant challenges remain in quantifying egg proteins in heated products. The adoption of optimized ELISA kits and better extraction methodologies could enhance analytical accuracy. The JRC emphasizes the importance of regular proficiency testing to maintain compliance with evolving WHO/FAO guidelines, ensuring consumer safety and the effective management of food allergens.    

Source:

MDPI