Dried Fruit - To soak or not to soak

Hi all

I read somewhere once that Raisins / Sultanas should be soaked before putting out for birds - so that is what I do and the Blackbirds and Starlings love them! I'm confused though as many brands of birdfood - including that sold by the RSPB have large tough pieces of dried fruit in them. Is this safe?

Any advice welcome

CJ