Coffee is not included in the list of allergenic ingredients as stated by the UK Government.

The full list of allergenic ingredients is as follows:

• Cereals containing gluten, such as wheat, rye, barley, oats, spelt, kamut and their hybridised strains
• Peanuts (also groundnuts)
• Nuts, such as almonds, hazelnuts, walnuts, Brazil nuts, cashews, pecans, pistachios, macadamias and Queensland nuts
• Crustaceans (includes crabs, lobsters, shrimps and prawns)
• Molluscs (includes mussels, cockles, oysters, scallops, squid and octopus)
• Sesame seeds
• Eggs
• Milk and milk products (including)
• Soy beans
• Celery
• Lupin
• Mustard
• Sulphur dioxide and sulphites at levels above 10 mg/kg or 10 mg/litre expressed as SO2

This relates not only to the ingredients (and their components) that are used in the product, but to anything that is still present in the final product, even in an altered form.