Why Allergen Testing Is a Matter of Life and Death

What Are Allergens and Why Are They So Dangerous?

Allergens are natural proteins that can trigger immune responses in sensitive individuals. Reactions range from mild itching to life-threatening anaphylaxis. The European Union has legally mandated the labelling of 14 allergens, including milk, nuts, gluten-containing cereals, and molluscs.

For a consumer with a peanut or milk allergy, even trace amounts can provoke a serious response. This places stringent demands on quality control, hygiene protocols, and product labelling.

Why Allergen Testing Is Essential

Quality professionals play a critical role in ensuring food safety, and allergen management is a key component of that responsibility.

The three main drivers for allergen testing are:

• Detecting and preventing cross-contamination
• Verifying labels and allergen claims
• Managing allergens as part of HACCP or food safety systems

Testing Methods and Their Technical Value

ELISA (Enzyme-Linked Immunosorbent Assay)

• Detects: Specific allergenic proteins
• Advantages: High sensitivity, applicable to a wide range of matrices
• Limitations: Proteins may denature during heating or processing and become undetectable

PCR (Polymerase Chain Reaction)

• Detects: DNA from allergenic ingredients
• Advantages: Can detect traces even in heavily processed products
• Limitations: Detects DNA, not the allergenic protein itself

Lateral Flow Devices (Rapid Tests)

• Detects: Usually proteins, similar to ELISA
• Advantages: Useful for quick decisions on the production floor
• Limitations: Lower sensitivity, especially in complex matrices

Mass Spectrometry (LC-MS/MS)

• Detects: Specific peptide fragments of allergenic proteins
• Advantages: Multiplex capability, high accuracy
• Limitations: Technically complex, costly, requires expertise

Technical Considerations

• LOD/LOQ: The Limit of Detection and Limit of Quantification determine the relevance of a method. An LOD of 0.5 mg/kg might suffice for "milk-free" claims but is inadequate for infant foods where stricter thresholds apply.
• Matrix Effects: Ingredients and processing (e.g., baking or frying) may affect detection. Validation at the product level is essential.

Legal Framework and Standards

The following regulations apply within the EU:

• Regulation (EU) 1169/2011 - mandatory labelling of 14 allergens
• Regulation (EC) 178/2002 - general food safety obligations
• Private standards - schemes like BRCGS, IFS and FSSC 22000 require documented allergen control as part of the FSMS

Overview of EU-Mandated Allergens (Regulation 1169/2011)

The following 14 allergens must be clearly declared on food labels:

1. Cereals containing gluten (wheat, rye, barley, oats, spelt, khorasan)
2. Crustaceans
3. Eggs
4. Fish
5. Peanuts
6. Soybeans
7. Milk (including lactose)
8. Nuts (almonds, hazelnuts, walnuts, cashews, pecans, Brazil nuts, pistachios, macadamias)
9. Celery
10. Mustard
11. Sesame seeds
12. Sulphur dioxide and sulphites (>10 mg/kg)
13. Lupin
14. Molluscs

Non-Regulated but Clinically Relevant Allergens

Besides the 14 mandated allergens, many other substances can trigger allergies or intolerances. These "emerging" allergens are not legally required to be labelled in the EU, but may still pose significant risks:

• Corn: IgE-mediated reactions reported
• Chickpeas: Common in hummus and vegan foods
• Lentils: Reported in Mediterranean and South Asian populations
• Peas (yellow/green): Cross-reactivity with peanuts possible
• Chestnuts: Cross-reaction with latex
• Sunflower seeds/oil: Reaction risk depends on refining process
• Durum wheat (pasta): Belongs to gluten-containing cereals
• Poppy seeds: Found in baked goods; rare, but noted
• Bamboo shoots: Anaphylaxis cases documented
• Citrus fruits: Cross-reactivity with pollen
• Strawberries/raspberries: Histamine-release (pseudo-allergy)
• Tomatoes: Latex-fruit syndrome linkage
• Rice: Clinically relevant in Asia
• Spices (curry, coriander, cumin, etc.): Frequent triggers, sometimes due to contamination

Cross-Reactions

Not all allergic reactions are caused by the food ingredient itself. Some occur due to:

• Latex-fruit syndrome: Cross-reactions with banana, avocado, kiwi, chestnut, tomato
• Pollen-food syndrome (OAS): Birch pollen allergy may cause reactions to apple, nuts, carrots, celery
• Insect proteins: Mealworms, grasshoppers, crickets-relevant for novel foods

Health Risks of Allergens

Allergens can lead to severe health effects in sensitive individuals:

• Mild: Itching, rashes, watery eyes
• Moderate: Diarrhoea, vomiting, shortness of breath
• Severe: Anaphylaxis, potentially fatal

Even trace amounts can be dangerous. Precision in testing and labelling is therefore not optional.

Allergen Risk Assessment as Core Element of Food Safety

Allergen management should be embedded in your food safety system as a risk-based approach.

How to apply this in practice:

• Identify allergenic ingredients: Map allergens per product line and category
• Conduct a risk assessment per process step: Receiving, storage, processing, changeovers, packaging
• Evaluate contamination routes: Air, personnel, equipment, rework
• Define control measures: Time/space separation, visual checks, validated cleaning
• Integrate allergens into HACCP: As CCP (for "free-from" claims) or operational PRP
• Link lab results to the risk matrix: Any unexpected positive requires root cause analysis and reassessment

The VITAL Approach

VITAL (Voluntary Incidental Trace Allergen Labelling) is a globally recognised system helping QA teams assess whether a precautionary allergen label (PAL) such as "may contain traces of..." is necessary.

VITAL supports:

• Risk assessment of cross-contact
• Calculating potential exposure per portion
• Decision-making on PAL requirements

How it works:

1. Identify potential cross-contact allergens: Consider raw materials, shared equipment, storage
2. Estimate exposure per portion: Use analytical data or estimations to calculate allergen load
3. Compare with VITAL Reference Dose (ED01): The dose at which 1% of allergic individuals may react
4. Use VITAL Decision Tree: Determine whether PAL is justified or avoidable

Conclusion

For quality professionals, allergens are not a paperwork issue but a core control point. Choosing the right testing method, interpreting results (including LOD/LOQ), and integrating allergens into your risk assessment are essential steps. A trace of egg or hazelnut can be deadly. That's why allergen testing is not a luxury, but a necessity.