weights and measures

[Mattk]

Just been up morrisons with my shopping list.I needed 400 ml of natural yoghurt but they stock it as a weight not a measure ie you buy 500grammes of yoghurt not x millilitres.

surely liquids should all be sold as a measure ? you dont buy a kilo of milk do you !

am i missing something ?

[kempie]

By convention it appears that "sticky" liquids are measured using 'dry measures' which are based on weight rather than 'liquid measures' which are based on volume.

Somebody, somewhere, must have defined how thick a liquid needs to be for it to become an honorary solid.

[Alltorque]

Solids and semi-solids are sold by weight. Yoghourt is a semi-solid, but don't know the formal classification rules. Sorry.

[rjkh]

Interestingly though, ice cream is sold in millilitres.

[Mattk]

...and cream !

thx for the answers guys.maybe they should put both units on the packaging.