No it's with accusative in this sentence.
smak=taste is accusative that is equal nominative because smak is masculine not animated
it would become genitive (smaku) if it were negative.
Dzieci nie lubią smaku lodów
But it's smak that is direct object of this sentence, while "lodów"= of ice cream describes taste, and is always in genitive. it can be also translated as ice cream's taste