Sir: As a person who works in the manufacturing chain for the main UK retailers, I find it difficult to understand why ‘may contain nuts’ is now becoming common in products not previously labelled as an allergen risk (‘Tesco defends ‘may contain nuts’ labels after backlash,’, 10 April).

The specs Tesco asks suppliers to complete ask for some very specific information regarding, among other things, nut policies. If we genuinely cannot guarantee there hasn’t been any kind of cross-contamination from any allergens and in this case nuts, we have to declare that. However, modern facilities and strict allergen segregation give enough assurance that the raw materials we are using would not have any possibility of cross-contamination.

It sort of makes a mockery of the information people are spending hours providing if this blanket labelling continues.

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