Add field for allergy information and other restriction labels

[bbastin]

Many visitors of canteens rely on allergy information and labels for vegetarian or vegan food for ethical reasons as well as other restrictions based on faith. If this would be added in a machine-readable way, applications could allow for filtering based on certain dietary restrictions.

[jgraichen]

We currently provide the notes fields for adding details, but not with defined values. At the time, no canteen provided machine-readable details, and we weren't aware of a standard?

Do you know of a standard we could embed in the XML feed format and the API?

[bbastin]

I personally do not know of any standard. Our canteens in Bonn provide allergy information in a way that is easily parsable, and because this is important information for many guests, I think it would make sense to expose it in a way where applications could filter for certain contents.

For labelling, I think it would make most sense to rely on the corresponding EU regulation 1169/2011, Annex II. I have seen multiple restaurants use this numbering system (Bonn uses one derived from this ordering), and this is a comprehensive list of allergens that need to be labelled. Both cereals and nuts also need a second level of subdivision, which is usually done with added letters in the order of them within the regulation (wheat: a, rye: b, barley: c, and so on).

Our canteen also labels more contents, namely garlic and the type of meat used in the food, so ideally, the system would be able to also allow for additional labels. Additives are also sometimes listed as well.

As for the encoding of the information, my first instinct would be something like this:

<contents>
    <allergen>1b</allergen>
    <allergen>2</allergen>
    <allergen>8a</allergen>
    <additives>E 392</additives>
    <note>Schweinefleisch</note>
    <note>Knoblauch</note>
</contents>

The allergens are listed with their respective number. The additives can be listed using the E number. The notes are additional information provided by the canteen, intended for human-readable information.