lower than expected SG

scottie · 06-01-2009, 10:06 PM

so i brewed up an ipa last night, my only issue was that my SG was lower than i expected... i got 1.042 and i was expecting more like a 1.050 or higher. i did have some boil-over, maybe 12 ounces total wort lost, maybe that has something to do with it... with it being in the fermenter now, i would assume its too late to compensate for it. but if i happen to run into a similar situation in the future, is it possible to adjust the SG once the wort is boiled? adding some sugar water maybe? thanks

malkore · 06-01-2009, 10:15 PM

sugar ferments completely.
Malt extract does not.

so, sugar will raise your Original Gravity, but can result in a lower Final Gravity.

Now that said...let me guess..you boil 2 gallons, then top off with 3 gallons of water in the primary?

If so you DID hit your OG. its very very hard to mix 2 gallons of wort into 3 gallons of water evenly. You get a non uniform solution, so your gravity reading is off.

You basically cannot miss OG in an extract recipe unless you don't add enough extract, add too much...or add too much/not enough water.

Extract has no efficiency like partial mash or all grain brewing...because the extract always gives you the same gravity. mashing does not.

scottie · 06-01-2009, 10:41 PM

good point, thanks, i didnt think of a non-uniform soultion. i do a partial extract 3 gallon boil and add 2, which would def lead to a non uniform solution. i did lose a small amount of wort and added a little water to get to my 5 gallons, and a non uniform solution, this must be the reason. as far as remedies for this issue, is there a formula or something, maybe an interesting project...

Twofox · 02-27-2010, 03:00 AM

The guys at the local brew shop said from the start to boil as close to the final recipe as possible. So a 5 gal boil is where it's at from what I understand.