Normalisation of data from allergens proficiency tests.

Area of Science:

• Food safety analysis
• Analytical chemistry
• Allergen detection

Background:

• ELISA kits from different manufacturers yield inconsistent allergen analysis results.
• This variability complicates proficiency testing, requiring separate assigned values for each kit.
• Existing methods lack standardization, impacting the reliability of allergen quantification.

Purpose of the Study:

• To investigate the use of a standardized calibrant for normalizing diverse ELISA kit data.
• To assess if a single calibrant can eliminate the need for kit-specific data differentiation in proficiency testing.
• To improve the consistency and comparability of allergen testing results across laboratories.

Main Methods:

• Three experimental Food Analysis Performance Assessment Scheme (FAPAS) proficiency tests were conducted (peanut, soya, gluten).
• A second spiked sample was included alongside standard spiked and unspiked samples.
• The ratio of results from the two spiked samples was analyzed to assess data normality.

Main Results:

• The ratio of results from spiked samples produced more normal and symmetrical data distributions compared to raw data.
• Raw data, often non-normal and multimodal, became more amenable to statistical analysis after applying the ratio method.
• The use of a single-point calibrant demonstrated the effectiveness of standardization in normalizing data.

Conclusions:

• Standardizing allergen analysis with a single calibrant effectively normalizes data from various ELISA kits.
• This method enhances data normality and symmetry, simplifying proficiency testing.
• Development of internationally recognized certified reference calibration standards is crucial for allergen testing laboratories.