Final Gravity

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kaiserben

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I had some distractions and complacency crept in, which saw me bottle a batch without remembering to measure final gravity.

How do I figure out what the gravity would have been before I bulk primed?

I bulk primed with 130g white sugar into 21L of beer. Gravity measured AFTER bulk priming is at 1.027 (my estimated FG was 1.015).
 
Go with estimations your in the ball park. 1.015 as good. Nothing bad could happen.
 
That amount of priming sugar will add about 3 gravity points, so you beer pre-priming gravity would be about 1.024, way above you target and likely to become bottle bombs.
 
1kg white sugar in 25L adds 1015 specific gravity. If yours was a 25L batch you would have added about 154gm sugar = 15.4% of 1kg (1015) = 2.32 gravity points x 1.1904 (21L into 25L) = 2.76 extra gravity points. So my calcs are that you added 3 gravity points with your 130gm white sugar making your pre-priming gravity 1024. If you didn't mash at a high temp then you may expect some problems from over carbonation.

EDIT - whoops initially mis-calculated the 21L into 25L, so edited to adjust
 
Well 2.5 points (FG 1.0245) Black n Tan is quite right I would be worried.
Mark

Actually 0.00241
M
 
Yikes! That'll teach me to not check gravity during a lager ferment.

It was a dark lager using 2 packs of rehydrated S-189.
I left it for 8 days at 13C.
Then let it rise to about 23C and left it for 11 more days (I'm surprised this didn't allow it to ferment out completely)
Then 7 days at 1C before bottling.

Dunno what to do now. Half bottled in glass, half in PET.
 
It could be that its fermented as far as its going to (down to bad mashing process which means a whole different conversation)
Keep an eye on the pet bottles if they start getting way too hard get the lot in the fridge asap and start drinking.

Considering how long it was at high temperatures I wouldn't expect the beer to carbonate very quickly.
Mark
 
It could also be (maybe I'm just wishing here) - because the sample was taken using the dregs from the bottling bucket - that there was a higher concentration of sugars and the reading is way false. It should have been well mixed, but you never know.

I'll do what MHB suggests and keep a close eye on the PET bottle firmness.
 
Can u loosen the lids, leave for enough time for them to ferment out the priming sugar and finish the ferment u didnt let them finish to begin with, and then prime again and cap?
 
MHB said:
Considering how long it was at high temperatures I wouldn't expect the beer to carbonate very quickly.
What does the high temperature do to cause a slow carbonation? Is it less residual CO2 or because it's a lager yeast? Not being a smarty, just curious. :)
 
More that the beer has already been sitting on the yeast at 23oC for 11 days. If it was going to get through the sugar quickly it would have - remember there is a lot less yeast in the bottle than the fermenter.

I suspect there is a process problem, either mashed too hot - low fermentable wort; unhealthy/unhappy yeast - lots of possible reasons; a bad calculation somewhere, mismeasuring something, fridge thermostat telling pork pies.... plenty of things can cause a low fermentable wort or poor fermentation

Would be surprised if all of a sudden the very small amount of yeast in the bottle jumped into action and ripped through all the remaining extract in a short time.
Mark
 
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