This is the 15373rd most frequent Polish word.
sokiem
"Sokiem" means "juice" in the instrumental case in Polish.
Here, "sokiem" is the instrumental case of "sok," used to describe the material or means by which something is made.
Napój jabłkowy zrobiono z naturalnym sokiem.
The apple drink was made with natural juice.
In this sentence, "sokiem" (instrumental case) indicates the agent or substance causing the effect (stain).
Proszę umyć ręce przed posiłkiem, są zabrudzone sokiem.
Please wash your hands before the meal, they are stained with juice.
Here, "sokiem" represents the instrumental case showing the means by which an action (topping the dish) is completed.