These days it is very important that it is clear what kind of allergens are in a product. People can be allergic to one or more allergens and if they eat something that contains one of the bad allergens, it can end very seriously. That is why it is very important to state which allergens are in a product. One way to do this is to do it with labels. If a dish is prepared with, for example, nuts, it is possible to stick a sticker on the packaging with “Allergens nuts” after the product is ready and packed. Also note that this also happens with products that do not contain nuts, but which are prepared in a place where you have worked with nuts, as it can also contain traces of nuts.