Freezing the fruit first will break the cellular walls of most fruit open like small berries or even crab apples and is very good to do if you dont have a press too do this for you so that the pectic enzyme can get in there and do its thing.
That's what I thought (have been doing this ever since joining this forum)... so this wouldn't have anything to do with gas in the wine later? What if you just started with the plain juice?