Selecting the right method or test kit for your food allergen testing

12 July 2023 | Marie-Anne Clarke, Laboratory Supervisor and Helen Arrowsmith, Regulatory Affairs Manager and Allergen Specialist

Food business operators must employ food allergen management systems to mitigate or remove potential sources of contamination and minimise allergen cross-contact risks. The control measures employed must be validated, verified, monitored and documented.

Within food allergen management, food allergen testing serves several purposes, including:

Demonstrating that controls and procedures in place to manage food allergens are working (such as validation and verification of cleaning to remove food allergens)
Providing evidence for compliance with claims
Assisting in investigations such as those into potential allergen cross-contact
Determining the food allergen status of raw ingredients

When selecting a food allergen test, you need to understand what you are testing for, why that specific test is being done, and on what type of sample

Worked example – selecting the right method for detecting milk cross-contact

Several tests are available for detecting constituents of milk. In the example table below, three different options are shown for comparison – an ELISA method for the detection of casein, an ELISA method for the detection of beta-lactoglobulin (BLG), and an ion chromatography method for the detection of lactose.

	Option 1	Option 2	Option 3
Test method	ELISA	ELISA	Ion chromatography
Test specificity	Casein	Beta-lactoglobulin	Lactose
Test measuring range	2-25 mg/kg casein	2.5-40 mg/kg BLG	20-100 mg/kg lactose
Measuring range in terms of skimmed milk powder (SMP)	10-125 mg/kg SMP	111-1778 mg/kg SMP	40-200 mg/kg SMP

To select the most appropriate testing option, the nature of the milk contaminant of interest should be considered. For example, whey powder has a high BLG content, making the ELISA test for BLG the most suitable choice if whey powder is the contaminant to be analysed for.

Skimmed milk powder (SMP), however, contains 20% casein, 2.25% BLG, and 50% lactose. Based on these proportions, it might seem like testing for lactose would be the most appropriate choice if SMP is the contaminant to be analysed for; however...

The sensitivity of the test needs factoring in, too. While SMP contains more lactose than casein, taking the sensitivity of the testing methods into account reveals that casein is actually the most appropriate marker for SMP in this example. Therefore, an ELISA test for casein would be the best choice in this case if SMP is the contaminant to be analysed for.

Scientist testing milk in laboratory. Scientist is pouring milk into glass jar

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End-product food allergen testing (including for other substances that cause food hypersensitivity) can to contribute to food safety through validation of your control processes, where feasible. While food allergen testing is an important part of any allergen management system, it is important to understand its limitations, select the right test for the application, and interpret results carefully (we can help with all of this).

If you need any information or support, get in touch.

Including food allergen testing, we provide a range of services to support your food allergen management needs, including; food allergen training courses, testing, and practical support with cleaning validation, hygienic design, food safety management systems, labelling and legislation.

About Marie-Anne Clarke

Marie leads the Allergen Testing and Biochemistry Molecular Biology teams. With over 20 years’ experience in analytical science, she supports food and beverage businesses through complex technical, regulatory and quality challenges, delivering practical, science-led solutions.

Her expertise spans analytical testing, allergen risk management, molecular detection methods, species authenticity verification, and GMO analysis. Marie works closely with manufacturers, retailers and ingredient suppliers to design and implement robust analytical testing strategies, validate laboratory methods, investigate contamination incidents, and interpret complex laboratory data to support compliance and risk mitigation.

Through consultancy projects, she helps organisations strengthen quality assurance frameworks, optimise testing programmes, troubleshoot analytical challenges, and align with UK and international food safety requirements.

She is experienced in allergen cleaning validation and verification (for both allergen management and reusable containers), laboratory best practice, and unravelling analytical results to enhance understanding.

Marie brings practical insight from hands-on analytical testing and consultancy assignments, sharing real-world case studies on risk management, regulatory expectations, method validation, and best practice in allergen and molecular testing strategy.