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Old 08-25-2007, 11:29 PM   #1
Jul 2007
Posts: 5


I just transfered my third batch of beer to the secondary fermenter and I have some questions about SG. My first batch I made an error in measurement and put in too much water so I had a very low starting gravity. The final product was a little diluted and probably very low alcohol but for a first batch, I think it turned out quite well.

I was more careful with the second and third batches and the starting gravity was normal in both cases: 1.050 for the Extra Special Bitter and 1.040 for the IPA. Both batches fermented in open primaries and as soon as the foam collapsed were siphoned into secondary fermenters. According to there instructions for both kits, the SG should be approximately 1.020 at this point, but for both it was much lower. The ESB had an SG of 0.012 when I put it in the secondary (all together It was 1 week in the primary) and 0.011 when I bottled it 2 weeks later. The IPA has been in the primary for 5 days and had an SG of 1.006 when I racked it today.

I'm curious why my SG seems to be dropping so much faster than what I read in books. Is this an indication of something wrong in my brewing process? The kits are from my local brewshop and use all malt, so there's no question of the amount of sugar to add. I pitched the yeast at 29 C for the ESB and 27 C for the IPA. Does anyone have any feedback on what might be going on here?

Thanks, M

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Old 08-26-2007, 03:44 AM   #2
malkore's Avatar
Jun 2007
Posts: 6,922
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books can only give you an average time frame.

I'm guessing you're fermenting at slightly above 'ideal' temps and thus your fermentations finish faster.

More importantly though, you need to wait for the beer to finish primary before you rack it. moving 'as soon as the krausen falls' is not a "surefire" method for success, especially as you start brewing bigger beers.

plus, some yeast strains krausen doesn't fall when primary is finished...instead it stays, protecting the beer.

you rack to secondary after 7-10 days (that's the minimum)...and once the hydrometer isn't falling anymore for 3 days' readings.

I will say 1.040 to 1.006 is pretty low...either you had a pretty attunuative yeast, or there could be a little something else in there eating the sugars up (wild yeast, etc).

Either way, I wouldn't worry about it. Just slow down on the racking, as pre-mature racking stresses the yeast, and stressed yeast produce off flavors.
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Old 08-26-2007, 01:46 PM   #3
david_42's Avatar
Oct 2005
Oak Grove, Oregon, USA
Posts: 25,599
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A faster ferment is good, unless it is so fast the wort over-heats. You pitched at high temperatures, which makes for fast yeast growth and starts the ferment quickly, but letting the ferment run at those temperatures will produce off-flavors.
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