Maybe I've misunderstood, but I thought f-packs ("finishing packs" or "flavour packs") were to add flavour, and sweetness after fermentation is complete. I guess my only experience with them is from a couple of kits I made. Does it really change the flavour of the finished wine if you put an f-pack into the primary and ferment it? Does fermenting 100% pure blueberry juice actually taste like blueberries? I know fermented grapes don't taste like grapes! I thought an f-pack was to put back some of the original fruit flavour that gets lost in fermentation.