I did my first brew in a bag a couple of weeks ago (i've done kits previously), and it's turned out great - much better than I expected! The only issue with it was that it produced about 4 gallons of wort, which was slightly reduced when boiling, then reduced again when tapping into the fermenter, and reduced again when transferring it to a clearing container (both times leaving behinds the "dregs"), and reduced again when bottling (again leaving the dregs behind), so it ultimately turned into about 3 gallons of bottled beer. It's lovely, much nicer than the kits, but I'd like to try for more next time.

I was thinking for my next one I would top the intial fermentation amount up to 5 gallons, since that's what my fermentation bin can contain, in order to end up with a bigger final yield. I've got a couple of bags of Youngs Brew Enhancer, which is a mix of dried malt and dextrose, and was thinking of adding a gallon of water plus some of that, into the wort, after boiling but before fermenting.

Questions: 1) how much, do you think? Each bag is a kilo. If I was making beer from a kit i would usually add a kilo of sugar to the liquid malt in the can, but I don't know if that's an appropriate comparison when i'm making my own wort.

2) Is after boiling the right time to put it in? Maybe I should add it to the wort before boiling, then add water to top it up to 5 gallons afterwards?

3) Is this just a terrible idea? Is it going to ruin the flavour?


  • 1
    Just thinking about this - did you account for the absorption of the grain in you recipe? It's about 1 litre of water per kilogram of grain.
    – Kingsley
    Commented May 11, 2020 at 22:09
  • With the previous one? I just followed the brew-in-a-bag instructions, which start out with 27 litres. I used 5kg of grain. I don't realy know why that yield was so low tbh, i just did another one and followed the same instructions and have about 25 litres in my fermenter now, without adding any extra water. I did add the brew enhancer though, we'll see what happens. Commented May 12, 2020 at 7:39

1 Answer 1


I would not do this. It probably wont "ruin" the flavour, but beer is a (sometimes delicate) balance of the sweetness of the malt against the bitterness of the hops. Your proposal is to add extra sweetness only.

I always try to brew the best possible beer. This means not cutting corners for the sake of a relatively small expense. You probably spent a couple of hours making the beer. Please don't spoil it for the sake of 10 grams of hops.

Take your recipe and just scale the whole ingredient list (including the hops and yeast) maintaining the ingredient ratios. If you need to split this into two brew-in-a-bag batches, then that's an easy fix which preserves quality.

  • 2
    I actually went for it last night with a whole 1kg bag, half at start of boil and half at end of boil. I will post here what happens. It's a brown ale, low on hops anyway, and if it ends up too sweet, but strong, I'll still be happy with it. I think my standards are lower than yours. :) Commented May 11, 2020 at 14:01

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.