"The guard wanted juice."
Translation:Vagten ville have saft.
There is a difference between juice and saft.
saft is what comes out of fruits when you squeeze them. This saft can be made into juice.
In a store, you'd buy appelsinjuice, æblejuice, abrikosjuice etc.
The words saft or saftevand also mean a fruit/berry drink that you dilute with water before drinking. I assume that's what the guard wanted.