Does hot water clean more efficiently than cold water?

Not with laundry, but when washing dishes? I just finished rinsing the crud from my juicer and as I was scrubbing away at the fruit pulp on the screen with a brush prior to actually washing it I thought of this. So it seems like an elementary science question, but is there a particular reason hot water breaks up and dissolves grime and stuff or is it simply a fallacy, and that water temperature has nothing to do with it. I know soap seems to lather up better in hot water, but what about just plain cold water vs. hot water? Any ideas?