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Old 05-21-2008, 09:32 PM   #1
cregan13's Avatar
Oct 2007
Raleigh, NC, Raleigh, NC
Posts: 32

My new lager is approaching 3 weeks in the primary. The bubbling in the airlock has slowed to about once every 25-30 seconds. The S.G. is 1.030 (i didn't take an o.g. - i am still learning). Is this a good time to start diacetyl? Will gravity continue to rise during diacetyl and secondary till it gets up in the 1.040 - 1.045 range? Any advice is appreciated.

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Old 05-21-2008, 09:55 PM   #2
david_42's Avatar
Oct 2005
Oak Grove, Oregon, USA
Posts: 25,599
Liked 158 Times on 148 Posts

Gravity goes down as beer ferments. 1.030 is very high for a finish gravity, so give it another 2-3 weeks.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"

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Old 05-21-2008, 10:15 PM   #3
Jan 2008
East coast, Virginia
Posts: 205

I'm learning as well. From what I gather, the finishing gravity for "most" common beers = 1.012 +/- a few points, so you do have a ways to go with that fermentation.
Also, the gravity Lowers as the sugar ferments into alcohol. Sugar suspends the hydromenter Higher (high numbers) after you boiled it.....then the yeast eat the sugar and Lower the numbers (lower gravity).
I'm unaware of gravity rising after the yeast is pitched, and the lid is snapped on.

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Old 05-22-2008, 01:58 AM   #4
Jul 2006
Posts: 156
Liked 3 Times on 1 Posts

for the future ... always make a big starter for lagers, crash cool it and pitch only the slurry, not the spent wort. if you pitch it COLD ... that is, about 45 or so and let the ferment rise to 50, you wont need a diacetyl rest at all.

if you are still bubbling twice a minute, the beer isnt done. don't even bother to take gravity reading unless its finished bubbling (and even this is no guarantee its done).

good luck

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