Originally Posted by CurtHagenlocher
So a sweet stout make with (say) 15% crystal might be too sweet and too malty and not creamy enough compared to one made with lactose?
I find that they affect the end product very differently.
Lactose has a creamy sweetness to it, that isn't really quite "sweet". Think of the sweetness of milk or cream. It doesn't feel the same on the palate as a similar amount of maltose.
I find that you can have far more lactose remaining in the final product than unfermented maltose, before the beer starts to be too sweet. I haven't used lactose in years though, and I can't really comment upon exact percentages of it. But the mouthfeel of a beer with crystal in place of lactose will have a different mouthfeel.