Why Is My Gravity Reading Off?


I recently brewed a stout with an extract/partial mash kit I got from my home-brew store.

The recipe used:

6 lbs LME syrup
3 lbs Munich malt extract
1 lb crystal malt
1 lb roasted barley
1 lb Chocolate Malt
1.5 oz Perle Hops
1 oz Palisades hops

I slightly modified the recipe by adding an additional: 1/2 lb of the chocolate malt, 1/2 oz of Rainier hops at the end of the boil, and a 90g 86% chocolate bar kinda fell in there too.

My question is that my gravity reading when it was all done and the wort had cooled only read about 1.055; whereas, the info sheet that came to me with the kit told me the gravity should be 1.077. Also, another weird thing, is that somehow instead of the 5 gallons that I was expecting, I ended up with closer to 7 total gallons. ABV should be around 7.3% One thing that did happen was that my grain bag melted open during the first part of the boil, and released a lot of the loose grain into wort that I later mostly filtered out.

What might have happened here? Am I screwed? Any way to fix this? It’s been a week now, and it does look to be healthily fermenting away with fervor. Should I be this worried, or might it turn out fine?


You would have had around a 1.077 gravity if you ended up with 5 gallons of wort. Because your wort volume was 2 gallons more than that, it cut your gravity back.

Either you mistakenly added too much water to the recipe before the boil, or your burner just doesn’t have as vigorous a boil as is common. If you did this beer on a stovetop, I’d expect that you’d lose less wort to boil off than if you used a propane burner.

It should be closer to 6%, but remember, your starting gravity is far lower than it would have been with only a 5 gallon batch. That’ll make your final ABV lower.

You may end up with a bit of astringency in your beer too because you ended up boiling those loose grains. When you boil grain, you release a lot of tannins into the wort. That’s why the recipe calls for removing the grain bag after steeping, before boiling your wort.

Your beer won’t come out as high in alcohol as you had hoped, but that’s not a big deal. You will probably notice some astringency in your beer, but that’s probably not a deal breaker either. Especially with all the flavor from those dark malts.

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