BrewersApprentice wrote:what would be the difference to the outcome if i use Dex or if i use Lactose?
Dextrose is an almost entirely fermentable sugar, so adds alcohol content to a brew. Because of this it also will make the end product drier than if it were left out.
Lactose, or milk sugar, is almost entirely
unfermentable, so adds sweetness but no alcohol content to a brew. I find that lactose will also add a slight sourness if used in too high a quantity so it's best to start with a lower amount in any given recipe and then experiment with greater quantities in subsequent batches if you want more sweetness.