Add Eurocode 2 groups as properties in the ingredients taxonomy

[stephanegigandet]

The Eurocode 2 classification is used by researchers. In particular it is used in the Nutri-Score specification to define what counts as fruits/vegetables/legumes:

"The list of ingredients qualifying for the “Fruit, vegetables and legumes” component has been revised
to include the following Eurocodes:

Vegetables groups
o 8.10 (Leaf vegetables);
o 8.15 (Brassicas);
o 8.20 (Stalk vegetables);
o 8.25 (Shoot vegetables);
o 8.30 (Onion-family vegetables);
o 8.38 (Root vegetables);
o 8.40 (Fruit vegetables);
o 8.42 (Flower-head vegetables);
o 8.45 (Seed vegetables and immature pulses);
o 8.50 (Edible fungi);
o 8.55 (Seaweeds and algae);
o 8.60 (Vegetable mixtures)
Fruits groups
o 9.10 (Malaceous fruit);
o 9.20 (Prunus species fruit);
o 9.25 (Other stone fruit);
o 9.30 (Berries);
o 9.40 (Citrus fruit);
o 9.50 (Miscellaneous fruit);
o 9.60 (Fruit mixtures).
Pulses groups
o 7.10 (Pulses)."

Adding Eurocodes groups in the ingredients taxonomy will ease the implementation of Nutri-Score and possibly enable other issues (e.g. for research).

Eurocode 2 documentation: https://web.archive.org/web/20200116170731/http://www.ianunwin.demon.co.uk/eurocode/docmn/ec99/ecmgintr.htm

Proposed implementation:

en:vegetable
eurocode_2_group_1:en: 8

<en:vegetable
en:root vegetable
eurocode_2_group_2:en: 8.38

<en:root vegetable
en:carrot
eurocode_2_group_3:en: 8.38.10

It's probably a good idea to add missing group 1, 2, or 3 entries (e.g. we currently don't have a "leaf vegetable" entry for group 8.10).

[github-actions]

This issue has been open 90 days with no activity. Can you give it a little love by linking it to a parent issue, adding relevant labels and projets, creating a mockup if applicable, adding code pointers from https://github.com/openfoodfacts/openfoodfacts-server/blob/main/.github/labeler.yml, giving it a priority, editing the original issue to have a more comprehensive description… Thank you very much for your contribution to 🍊 Open Food Facts