In mid-April 2026, Marks & Spencer recalled their Authentic Greek Yoghurt with Vanilla after discovering that the product contained undeclared gluten. For anyone managing allergen control in a food factory, this is not a labelling mistake—it is a breakdown in the Hazard Analysis and Critical Control Point (HACCP) system where allergen detection and control should have prevented the product from reaching consumers. This article examines what went wrong, where HACCP failed, and how dairy manufacturers can strengthen allergen management in their own facilities.
What Happened
Marks & Spencer Authentic Greek Yoghurt with Vanilla was recalled after allergen testing revealed the presence of gluten, which was not declared on the product label. Consumers with celiac disease or gluten sensitivity who purchased this product were at direct risk of adverse health effects. The FSA alert (issued 18 April 2026) recommended that consumers with gluten intolerance avoid the product and return it to the retailer for a full refund.
Unlike some allergen incidents involving cross-contact in shared manufacturing equipment, this case suggests either:
- An ingredient supplied as "gluten-free" was contaminated or mislabeled
- Incoming ingredient testing or supplier verification failed to detect gluten
- Formulation or recipe data was not updated correctly when an ingredient was changed
The precise root cause has not been publicly disclosed, which means we must work from the evidence to infer where the HACCP system failed.
What Went Wrong—Root Cause Analysis
This is a failure in Codex Principle 1: Hazard Analysis, specifically the assessment and control of allergen hazards. The likely failure sits in two places:
1. Allergen Source Control (Likely CCP or OPRP)
BRC Issue 9 Section 5.3 (Allergen Management) requires that:
- All ingredients are assessed for allergen presence (clause 5.3.2)
- Suppliers provide documented allergen declarations (clause 5.3.3)
- Incoming ingredient testing or verification confirms the allergen status
If gluten was present in an ingredient that should have been gluten-free, the manufacturer did not:
- Request explicit allergen test results from the supplier, OR
- Test incoming ingredients for gluten contamination, OR
- Verify that the supplier's allergen declaration matched the actual product composition
This is a CCP-level control (critical to food safety) because allergen presence directly determines whether the product is safe for allergic consumers. The monitoring point should have been: "Allergen status of each ingredient lot verified by supplier declaration AND incoming ingredient testing."
2. Formulation and Recipe Control (PRP)
If an ingredient was recently changed (e.g., a new supplier, a new gluten-containing additive), the hazard analysis was not updated and the new ingredient was not assessed for allergen content. This violates Codex Step 5 (Identify the hazards and preventive measures) and BRC 2.14 (Management of Change). Specifically:
- The change should have triggered a HACCP review
- New allergen hazards should have been identified
- New controls (testing, supplier verification) should have been implemented before production
3. Documentation and Traceability (PRP)
The facility's allergen matrix or ingredient specification document was either:
- Not updated when the formulation changed
- Incorrect or not consulted during production
- Not cross-checked against the product label before release
This suggests a breakdown in documentation control (BRC 8.2) and product release procedures (BRC 7.2).
How This Should Have Been Prevented
A dairy manufacturer managing gluten as an allergen hazard should have implemented these specific controls:
1. Supplier Allergen Verification (Monthly for each ingredient)
Before any ingredient enters production, the Quality Manager must:
- Request a written allergen declaration from the supplier covering ALL allergens on the FSA's 14-allergen list (cereals/gluten, eggs, milk, nuts, sesame, etc.)
- Retain the document on file with batch number and date
- Identify any ingredient that contains or may contain gluten (e.g., certain thickeners, starches, or flavoring compounds used in yogurt cultures)
- Red-flag any change in supplier or ingredient specification and treat it as a change requiring HACCP review
This is not a one-time activity—supplier allergen declarations must be refreshed when batches change or ingredients are reformulated.
2. Incoming Ingredient Testing (Every lot for high-risk ingredients)
For ingredients where gluten risk is significant (e.g., starch-based thickeners, additives sourced from grain-processing facilities), the lab should conduct:
- Gluten ELISA testing (threshold: <10 ppm for "gluten-free" labeling)
- Testing records must be retained and linked to batch numbers
- Any lot failing gluten testing must be quarantined immediately—do not release to production
A rapid result turnaround (24 hours) is essential; do not rely on supplier certificates alone for allergen-sensitive products.
3. Ingredient Specification and Allergen Matrix (Updated within 48 hours of any change)
The Quality team must maintain:
- A current ingredient specification document that lists allergen status (contains, may contain, free from)
- An allergen matrix showing which products contain or may contain each of the 14 major allergens
- A verification step: before ANY formulation change, re-run the allergen matrix to identify new hazards
- Sign-off by the Technical Manager or Quality Manager confirming the new allergen status is accurate
4. Product Release Checklist (Every batch)
Before batch release to QA:
- Verify the formula used matches the current ingredient specification
- Verify the product label allergen declaration matches the formula and the allergen matrix
- Confirm all incoming ingredient test results are available and pass criteria
- Sign and date the release checklist; do not rely on memory or informal notes
5. Consumer Complaint Response (Immediate)
If a consumer or retailer reports an allergen incident, the response protocol must:
- Halt all batches of that product immediately
- Trace the affected ingredients back to source
- Request urgent allergen testing if not already available
- Notify the FSA within 24 hours if allergen presence is confirmed
- Do not wait for internal audit—act immediately
Strengthening Your Allergen Management With SafetyCore
When you build a HACCP plan in SafetyCore, the allergen management controls are structured and enforced at every step:
Hazard Analysis Layer
SafetyCore's hazard analysis builder forces you to list every known allergen for each ingredient and product. You cannot mark a hazard as "controlled" without specifying the preventive measure (e.g., "Incoming testing, <10 ppm gluten"). This removes the risk of an allergen being overlooked or forgotten when staff change or when a formulation is updated.
Supplier Verification Integration
SafetyCore's supplier module links ingredient batches to allergen declarations. When you record a new ingredient lot, you must attach or reference the supplier's allergen certificate. This creates an audit trail that an EHO or auditor can follow: ingredient → batch → supplier document → test result → batch release.
Triggered Change Review
If a formulation changes (new supplier, new ingredient), SafetyCore flags this automatically and initiates a structured HACCP review against the current hazard analysis. The review step includes a mandatory re-check of the allergen matrix, ensuring no new allergens slip through.
Batch Release Checklist
SafetyCore's batch tracking system includes a final release stage where you confirm:
- Allergen test results are available and linked to the batch
- Supplier allergen declaration is current and on file
- Product label matches the approved formula allergen status
- Any deviation is logged and requires manager approval
This checklist is immutable—once signed, it becomes part of the regulatory record. If an enforcement officer or auditor reviews your records, they see every batch release decision and the evidence backing it up.
The Bottom Line
The Marks & Spencer gluten recall is a reminder that allergen control is not an afterthought to label design—it is a critical HACCP control point. The fact that a major retailer's product reached shelves with undeclared gluten indicates that hazard analysis, supplier verification, and product release procedures failed at one or more points. For UK dairy manufacturers, the lesson is clear: treat allergen hazards with the same rigor you would apply to pathogenic bacteria. Implement monthly supplier allergen verification, test every high-risk ingredient lot, maintain a current allergen matrix, and enforce a batch release checklist. Do not rely on informal knowledge or assumption. The next consumer affected by undeclared allergen could pursue a claim against your company—and more importantly, could suffer a serious allergic reaction. Review your allergen risk assessment against BRC 5.3 this week. If you're using SafetyCore to document your HACCP system, the allergen controls are built into the platform so nothing falls between the cracks.
If you're reviewing your allergen management system, SafetyCore gives you a structured way to document and enforce every control—from supplier verification to batch release. Start a free trial at safetycore.co.uk.