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Old 03-12-2009, 11:28 PM   #1
Feb 2009
Posts: 68

I just checked my IIPA and noticed that the constant off gassing and swirling had settled to just very fine particles falling compared to those rising.

So it has been 2 1/2 weeks so i sanitized my wine thief and checked the Specific Gravity.

was 1.024. So i did the conversion of OG (1.084) - FG(1.024) * 133 = ABV.

Im not saying thats my Fg but if it was im sitting on 8% alcohol. The directions said the estimated ABV would be between 7 - 8 %.

So i went ahead and added my dry hops , which directions say leave in there for 10-14 days to settle, and was wondering how I could determine my Attenuation.

The recipe was 12lbs Ultra Light LME

Had 3 hop additions one at 60 one at 30 and one at 15 mins remaining in boil.

Boiled with 3 1/2 gals water topped off with one gal water in fermenter.

Used a 2L starter which had 2 vials White Labs Cal Ale yeast and pitched at 66 degrees.

Fermented for 2 weeks at 68 ( actual Ferm Temperature Not Ambient ) and then 2 days at 72 and the last 2 days 68.

Tasted my Sg Sample and its going to be good, very hoppy and nice, and was just wondering how my attenuation is.

If i had to guess id say 72 - 74% attenuation which is in the upper realm of what the company said the yeast could do.

Hows everything ive done so far sound?

( Thanks to all who have helped on my other posts, ive learned a lot with only posting a few questions )

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Old 03-12-2009, 11:37 PM   #2
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Jun 2006
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If you're at 1.024, that's about 70% attenuation, with an ABV of just under 8% (7.9 by my math).

California ale yeast usually gives me closer to 80% attenuation, but I think the relatively high ABV must have slowed it down for you. I still would have expected it to go lower, though- maybe as low as 1.016.
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Old 03-13-2009, 12:12 AM   #3
Feb 2009
Posts: 68

I was accidentally confused 2 yeast strains i had written down in my note book.

Cal Ale yeast has an attenuation of 73-80%.

Using the Apparent Attenuation Calulation

AA = ( 1 - (FG-1) / (OG - 1) * 100

Im at 71%.

Im sure I can eek out some more points just worried I may have added my Dry Hops too early.

However, I do not see how this style with the recipe can say an estimated ABV of 7.5% which would put the attenuation even lower.

I know I wont hit above 75% , maybe near it but maybe with the alcohol level the yeast wont do much more.

Im feeling good about this batch but since the Dry Hops will be in there for 2 weeks ill know what the FG is come bottling time.

If I put them in too early then I wouldve lost some aroma but nothing more.

The sample tasted great, just like the IPAs I love but only time will tell if ill hit the IBUs of a True IIPA. ( This I doubt because i have to do partial boils and do not have the room nor equipment for full boils )

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