Products quantities

How to handle it

Existing libraries to parse weights and quantities

• https://github.com/iancanderson/ingreedy

Using Wikidata

• Translations and aliases of units
  • List of Units in multiple languages on Wikidata

• weight unit list
  • Units of weight list on Wikidata
• units of volume
  • Units of volume list on Wikidata

Possible calculations

• Weight per item
  • Is the same item always the same weight (ham slices)
  • Useful if you eat one of the cakes in the packaging, and want to know how many calories you ate without having to weight the cake
• Percentage of water
  • Useful to calculate actual cost if we know the price
  • Useful to fix calorie calculation for some products
• Calculate packaging weight by making the difference between actual weight and advertised weight
• Calculate weight per volume for products (1dL of water is 1kg, but this changes for various products that also have a mention of their volume)
• Some products will have multilingual weights
  • we can check that the conversion is well done if we have both values
  • we can display the value in several metrics if we have a sanitized value in one metric

Canonical approach

The real-world quantities for products as used by the user (and printed on the packages) is not ideal. It is often impossible to parse the quantities and understand what is indicated. However it is possible to find some common approach. This is a first attempt.

Some remarks:

• product central - any quantity that is indicated is about the product and not the packaging;
• equivalents - one or more equivalents might be available, i.e. in grams, oz or liters, 24 cookies / 6 cookies in 4 packages;
• containers - the generic toplevel package is a container;
• subcontainers - a container might comprise multiple subcontainers (or even subsubcontainers) [hierarchy?/taxonomy?]
• (sub-)container synonyms - a user might container other words to describe a container, such as bottle, can, bag, etc. [hierarchy?/taxonomy?]
• defaults - in indicating the quantity some parts are assumed to be understood. If it states 33cl it is assumed to be about the container (the bottle) and the product (beer);
• components - a product might consist of multiple components, which must be combined to get the product. Cf Creme brulee = vanilla cream + caramel flakes (to be heated).
• subproduct - sometimes a subproduct quantity is indicated (net/brut, egoutté/drained);
• verbosity - the language used in specifying quantity must be translated to a parsable format;
• scattered - all information necessary to fill the entire quantity formula might be scattered over the package.
• detail quantities - sometimes a detailed quantity might be present (1 biscuit weighs 23g) and a multiplier is needed to get the total weight of the package;
• marketing - some quantities are added for marketing purposes, extra 25g;
• subsubcontainers - an extra subdivision, eg 1 carton of yoghurt with 2 layers and 8 pots per layer;

Generic formula

Any generic quantity formula should reference the product(-name), the container and a volume or weight measure. The productname and container should (?) reference the corresponding fields.

The quantity formula is:

container_multiplier x container_name x product_multiplier x (sub_)product_name x quantity_value x quantity_unit

For example:

• 1 bottle of red wine comprising 70 cl (on the bottle indicated as "70 cl");
• 1 package of granola cookies with a total weight of 276 g (just printed as 276g), which is equivalent to:
  • 1 package of 12 biscuits with a total weight of 276g, which is equivalent to:
  • 1 package of 12 biscuits with an individual weight of 23g per biscuit.

Practical usage

In practice however other indications are used by users. There is no best practice defined.

• to indicate times, either a "*" or a "x" is used;
• equivalent formulas are distinguished by a ";" or brackates "(,)"
  • multiplier indicates how often a quantity unit is used, i.e. 6 (25 cl bottles). This is a number.
  • quantity the size of the units in size_units, i.e. 25 (size) cl (size_unit) bottles (units). This is a number.
  • size_units is the unit for the size parameter, i.e. kg, ml or cl. This is an enumerated?
  • unit is the element the numbers and sizes refer to, i.e. pot, bottle, sack, etc.

Test approach

To test this approach the examples found in France have translated to this formal approach:

Quantity as stated by user	Container multiplier	Container name	Product multiplier	Product name	Quantity value	Quantity unit
1 kg (8 pots) - [2 x (4 x 125 g)]	8	pots	-	-	1	kg
or	2 x 4	pots	-	-	125	g
275 g [250 g + 25 g (10 %) gratuit]	-	-	-	-	275	g
or	-	-	-	-	275 + 25	g
2 * 400 g (800 g)	2	-	-	-	400	g
or	-	-	-	-	800	g
4X100g	4	-	-	-	100	g
2*25g	2	-	-	-	25	g
200 g [160 g (2 x 8 pièces) mini-nems + 40 g sauce nuoc mâm]	-	-	-	-	200	g
or	-	-	2x8	mini-nems	160	g	+
or	-	-	-	sauce nuoc mâm	40	g
211,5 g (9x23,5g)	-	-	-	-	211,5	g
or	9	-	-	-	23,5	g
220g (2 unités, 2 x (60 g + 50 g))
2 x 21.5 g = 43 g
300 g (15 biscuits de 20 g)
1 Litre	-	-	-	-	1	litre	-
18tranche	-	-	18	tranches	-	-
375 g, 30 pièces	-	375	g	-
or	30	-	-	pièces
240 g (12 Portions)	-	240	g	-
or	12	-	-	portions
400 g (12 à 18 bouchées)
Poids net 190 g, poids net égoutté 140 g
contenance : 4250ml, poids net total : 4000g, poids net égoutté : 2210g
3 x [200 g (130 g net égoutté), 212 ml]
330 g (dont 180 g net), 370 mL
28 g - 20 dragées	-	28	g	-
or	20	-	-	dragées
260 g (26 portions de 10 g)
130 g pour 20 galettes	-	130	g	-
or	20	-	-	galettes
280 ml - 310 g	-	280	ml	-
	-	310	g	-
25 sachets	25	-	-	sachets
220 g (1 personne)	-	220	g	-
128 g (16 bâtonnets de 2 cubes)	-	128	g	-
	16	-	-	bâtonnets
	16x4	-	-	cubes
12 (calibre Moyen => 53 à 63 g)	12	-	-	calibre moyen
8 sachets de 4	8	-	-	sachets
	8x4	-	-	-
400 g, 425 ml (3 douzaines)
228g (4x57g) / 48 cl (4x12cl)

Countries

France

Product name	Quantity as stated by user	Product page URL
Brassé nature	1 kg (8 pots) - [2 x (4 x 125 g)]	(link)
Emmental Coeur de Meule (28 % MG)	275 g [250 g + 25 g (10 %) gratuit]	(link)
Basilico	2 * 400 g (800 g)	(link)
Frais Malo Sucré	4X100g	(link)
Twix	2*25g	(link)
16 mini-nems Poulet, menthe, Légumes, coriandre - Précuits - Surgelés	200 g [160 g (2 x 8 pièces) mini-nems + 40 g sauce nuoc mâm]	(link)
9 barres au chocolat au lait et aux céréales	211,5 g (9x23,5g)	(link)
Fondant au chocolat	220g (2 unités, 2 x (60 g + 50 g))	(link)
Kinder Bueno	2 x 21.5 g = 43 g	(link)
Prince Goût Chocolat	300 g (15 biscuits de 20 g)	(link)
Eau minérale Contrex	1 Litre	(link)
Brioche Harrys Tranchée la recette Originale	18tranche	(link)
FERRERO ROCHER Boîte de 30	375 g, 30 pièces	(link)
Kiri® (32 % MG) à la crème de lait	240 g (12 Portions)	(link)
Bouchées de Poulet à la provençale	400 g (12 à 18 bouchées)	(link)
Thon entier au naturel	Poids net 190 g, poids net égoutté 140 g	(link)
Haricots beurre très fins	contenance : 4250ml, poids net total : 4000g, poids net égoutté : 2210g	(link)
Lentilles (Lot de 3 boîtes)	3 x [200 g (130 g net égoutté), 212 ml]	(link)
Délices du Potager - Mini poireaux	330 g (dont 180 g net), 370 mL	(link)
Chewing Gum Hollywood	28 g - 20 dragées	(link)
Fruit d'Or pro-activ® (35% MG) Tartine 260 g - Unilever	260 g (26 portions de 10 g)	(link)
Galettes, tout au beurre	130 g pour 20 galettes	(link)
Ketchup P'tits Heinz	280 ml - 310 g	(link)
Original Earl Grey	25 sachets	(link)
Cappellettis Tofu, Epinards Bio - 220 g - Céréal Bio	220 g (1 personne)	(link)
KUB ® Or	128 g (16 bâtonnets de 2 cubes)	(link)
Oeufs de poules Elevées en Plein Air (x 12) calibre Moyen - Carrefour	12 (calibre Moyen => 53 à 63 g)	(link)
Belvita sablé lait	8 sachets de 4	(link)
Escargots de Bourgogne Extra Gros - 400 g - E	400 g, 425 ml (3 douzaines)	(link)
nestle	228g (4x57g) / 48 cl (4x12cl)	(link)