An allergen matrix is one sheet with every dish down the side and the 14 regulated allergens across the top. It exists so that any member of staff, on any shift, can answer an allergen question the same way — from a document, not from memory.
It is not itself named in law. What the law requires is the information behind it: for some of your food, printed on the pack; for the rest, available accurately and consistently on request. The matrix is how a working kitchen holds that information in one place.
The list comes from Annex II of Regulation (EU) No 1169/2011, which is retained in UK law. Government guidance states them as: "celery; cereals containing gluten (such as wheat, rye, barley and oats); crustaceans (such as prawns, crabs and lobsters); eggs; fish; lupin; milk; molluscs (such as mussels and oysters); mustard; peanuts; sesame; soybeans; sulphur dioxide and sulphites (at a concentration of more than ten parts per million); tree nuts (such as almonds, hazelnuts, walnuts, brazil nuts, cashews, pecans, pistachios and macadamia nuts)".
Four points on that list catch kitchens out.
Annex II also carries specific exemptions — refined soybean oil, barley-based glucose syrups, fish gelatine used as a carrier, whey used for spirits. Read them once rather than assuming; most of them will never apply to a restaurant kitchen.
Natasha's Law is the popular name for a change to labelling rules for food that is prepacked for direct sale (PPDS) — food you pack on the same premises you sell it from, before the customer orders it. Sandwiches made in the morning and stacked in the chiller, salad pots, wrapped cakes on the counter.
Before the change, that food could be sold with no ingredients label. Since the change, it must carry the name of the food and a full ingredients list, with any of the 14 allergens emphasised inside that list.
It is worth knowing there is no single UK statute. There are four separate instruments, one per nation, and all four came into force on the same day — 1 October 2021:
Each one works the same way: it inserts a new regulation 5A (ingredients list, including allergens, directly on the package or on a label attached to it) and a new regulation 6A (the name of the food, same placement) into that nation's Food Information Regulations 2014. If you trade across the border, you are complying with two instruments that happen to say the same thing — but FSA guidance covers England, Northern Ireland and Wales only. Scotland is Food Standards Scotland's territory, so check guidance from the right regulator.
The test is whether the food was packed before the customer asked for it, on the premises it is sold from.
Usually PPDS: sandwiches, wraps, salad boxes and pasta pots made in the morning and put out in a chiller; pies, sausage rolls and quiche wrapped and shelved; cakes and traybakes boxed on the counter; sauces and dressings decanted into pots and put on display.
Usually not PPDS: a dish cooked to order and served on a plate; food a customer chooses loose and you bag in front of them; food packed at a different site (that is straightforward prepacked food, which has always needed a full label); a takeaway assembled after the order is placed.
The awkward cases are worth deciding in advance and writing down: the pre-made sandwich that is toasted to order, the salad that is dressed at the pass, the daily-batch soup ladled into a pot at the point of sale. Decide, record the reason, and label consistently.
For food made to order and served without packaging, the rules are different and often misread as "no rules". Allergen information still has to be provided, and it has to be accurate. The FSA's technical guidance is explicit that businesses "have flexibility to provide allergen information for non-prepacked food by any means, including orally by a member of staff", but adds that where a business chooses to provide it orally, it "must use clear signposting to direct the customer to where this information can be found".
So a chalkboard line telling guests to ask a member of staff is a legal requirement in that model, not a courtesy — and the staff being asked need something authoritative to read from. That is the matrix.
On a PPDS label, allergens must be emphasised within the ingredients list. FSA technical guidance summarises the requirement as Article 21 specifying that the Annex II ingredients "will need to be emphasised from the other ingredients within the ingredients lists by means of contrasting font, size, style or background colour". The business chooses the method — bold, capitals, underlining or a contrasting colour are all accepted — and on PPDS the guidance states that the allergenic ingredients "must be emphasised every time they appear in the ingredients list", not just the first time.
Two practical consequences. Emphasise the allergen word inside the compound ingredient — "mayonnaise (rapeseed oil, EGG yolk, mustard)" — rather than tacking a separate allergen line on the end. And pick one method and use it on every label; mixed conventions across a chiller look like an error to an inspector and read like one to a guest.
Precautionary labelling — "may contain" — is worth its own rule. FSA technical guidance is restrictive about it: such a statement "should only be provided with prepacked or non-prepacked foods if an unavoidable risk of allergen cross-contamination has been identified following a risk assessment that cannot be sufficiently controlled through controls, such as segregation and cleaning". Read that in order. The risk assessment comes first, then the controls, and the warning is what is left when cleaning and segregation genuinely cannot fix it. A blanket "may contain everything" on every label is not caution; it removes the customer's ability to eat with you and it tells an inspector no risk assessment was done.
The same document that lists every ingredient in every dish is also the document that costs them. If you are rebuilding recipe specs for allergens, do the costing in the same pass — you already have the pack sizes and quantities open in front of you.
Cost a dish with the free food cost calculator, scale a batch recipe with the recipe costing tool, or start from a ready-made 14-allergen grid in the PrepSheet templates.
This is a working chef's summary of the rules as they stand, not legal advice. Your local authority environmental health team is the body that will inspect you, and they will answer questions before a visit as readily as after one.