"We have drunk orange juice."
Translation:Wypiłyśmy sok pomarańczowy.
It would sound as if you're describing the juice, and with this particular flavour, which is also a colour - as if you were saying that the juice had orange colour. Many foods names are kinda 'set phrases' and have the adjective on the second position, like for example "ser żółty".
"Jabłkowy sok" wouldn't have anything to do with any colour, but still would sound a bit off. "Sok jabłkowy" is simply "apple juice". Some natives could probably use your word order ("żółty ser" is actually not that bad), but it's really better to stick to what is most natural.
That's so interesting. I compare it to Russian, but it's the complete opposite. The fruit orange and the color orange are different words so apiel'sjinowyj sok is orange juice, and oranżewyj sok is juice that is orange. Apple juice is jabloćnyj sok and yellow cheese is zoltyj syr.