What the rules require at a banquet service
European regulation 1169/2011 does not distinguish between a restaurant and a banquet: for food sold without packaging, information on the fourteen declarable allergens has to be available to the final consumer. It can be given in writing or verbally, provided that in the second case there is an accessible, verifiable written source behind it.
The practical translation for a caterer: it is not enough that the head chef knows. There has to be a document — or its digital equivalent — where what each dish contains is written down, and that document has to be producible.
The difference between informing and tracing
Informing means the composition of the dish is available: what is in the main course, whether the sauce contains mustard. It is an obligation about the product, and it is met with a technical spec for each preparation.
Tracing is something else: being able to say, of Saturday’s event, who declared what and what was done with that information. It is not exactly what the regulation demands, but it is what gets asked for when something goes wrong, and it is what separates a caterer who can explain what they did from one who can only say they did it properly.
The record that saves you: who, which table, which allergen
One document per event with three columns. No more is needed, and with less it does not work: a name on its own does not say where the person is, and a table on its own does not say who to look at.
That document does two jobs at once. Before the event, it is what the kitchen uses to prepare the special plates and count them. During service, it is what the head waiter carries to know that on table 7, seat 4, there is somebody gluten-free and that the plate comes out marked.
Getting it to the floor without losing it
The point where this almost always fails is not the kitchen: it is the handover to the floor. The special plate is prepared correctly and arrives at the wrong table, or arrives at the right one and whoever serves it does not know which of the ten diners it belongs to.
What works is for the information to travel with the plan: the same document that says where everybody sits also says who has a requirement. That way, whoever serves table 7 does not have to remember anything; it is in front of them on the sheet they are already carrying. Marking the plate in the kitchen and not marking the seat on the plan is half the job.
What to keep after the event
The event’s requirements list, the specs for the dishes served, and the plan with the seat assignments. The three together reconstruct what was served, to whom, and with what information — which is exactly what gets asked if there is a complaint.
On how long to keep it, the rules do not set a period for this particular document. The prudent approach is to align it with whatever already applies to the establishment’s food safety records, and in any case to have it written down rather than depending on whether somebody filed the folder.