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Old 05-12-2012, 12:53 PM   #11
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Did you use the refractometer tool to adjust your final gravity reading??? Alcohol throws off your readings considerably, Beersmith (I'm sure elsewhere does also) has a correction calculator for this... for instance, my IIPA that I just kegged, started out reading 1.087 with my refractometer (correct), and the FG read something like 1.038, but when you factor in the alcohol, and run your correction the ACTUAL FG was like 1.010.

Just a thought.

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Old 05-12-2012, 01:04 PM   #12
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Originally Posted by mjkinne23 View Post
I used a refractometer to take all my readings.
That explains it, then. A refractometer is great for pre fermentation readings, but alcohol skews the light refraction (which is what a refractometer measures), so you should take the FG with a hydrometer.

There ARE calculators to guestimate the "real" reading if you enter the original reading, but they are not all that accurate.

Next time you open a beer, pour some in a testing flask and shake it to decarb. Let it warm, and then take the SG when it's flat. That will be the correct reading.
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Old 05-12-2012, 11:38 PM   #13
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Originally Posted by Yooper

That explains it, then. A refractometer is great for pre fermentation readings, but alcohol skews the light refraction (which is what a refractometer measures), so you should take the FG with a hydrometer.
So I clearly made a rookie mistake when calculating my post fermentation gravitates but is it really as simple as not having let it ferment long enough? I know readings are the only true way to know when it is over but it had been two weeks of very active fermentation and the foam had fallen back in on itself. It was as least as active as all my extract batches. Hard to imagine it still had that far left to go.
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Old 05-13-2012, 12:31 AM   #14
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Originally Posted by mjkinne23 View Post
I made a 5 gallon Dunkelweizen, the grain bill was:

6lb white wheat
4lb 2 row
8oz caramunich
4oz pale chocolate
4oz carafa special II

My pre-boil gravity was 1.046 and into the carboy it was 1.054, target OG was 1.050-1.052. When I racked it was 1.032 but when I bottled it was 1.40 (one was a bad reading?).

Can't thank all of you enough for your help!
You say the gravity when racking was 1.032. If you were using raw wort (i.e. no alcohol) conversions, that would translate to a brix reading of 8.25

If you started with an OG reading of 1.054 (brix 13.75), then a brix reading of 8.25 after 2 weeks of fermentation would indicate a SG of 1.020 according to Promash.
However, as Yooper said, the conversions from brix to SG after fermentation has started are not necessarily accurate, and it could be a few points higher or lower than 1.020, but 1.020 is certainly closer to the mark than 1.032.

-a.
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Old 05-13-2012, 11:04 AM   #15
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1.020 is certainly closer to the mark than 1.032..
Thanks a. So other than correct readings, any suggestions on what to do differently with the next batch to produce some actual alcohol?
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Old 05-13-2012, 11:43 AM   #16
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If the beer is good just drink it with you favorite shot I have tried to do opposite buy mashing hotter on my last batch. I am a light wight and love sweeter beer.

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Old 05-13-2012, 11:54 AM   #17
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I'm no expert on wheat beer, but isnt there another step with wheat? I'm pretty sure you need to "cook" the wheat first so it will release the starches to be converted by the enzymes in your malts. Also I think your mash time needs to be extended?

make sure you have a good mash tun and make sure you take into account the temp absorption that your tun is going to take out of your mash water. i have taken heating my mash tun to the approximate temp by putting hot water in it. this will help with temp control. my tun drops 1 or 2 degrees over an hour.

oh, and you probably do have ok abv - off the top of my head, probably 4.5% or so

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Old 05-13-2012, 12:16 PM   #18
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Thanks a. So other than correct readings, any suggestions on what to do differently with the next batch to produce some actual alcohol?
What do you mean? You started with an OG of 1.054 and the FG is less than 1.020 (but we don't know the exact reading until you take one). Remember that your last refractometer reading is useless, but since it was post-fermentation and it probably calculates to less than 1.020, that's the figure we can use for sure.

That's at least 4.5% ABV and it is probably higher, depending on the actual FG reading.
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Old 05-13-2012, 12:17 PM   #19
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I'm no expert on wheat beer, but isnt there another step with wheat? I'm pretty sure you need to "cook" the wheat first so it will release the starches to be converted by the enzymes in your malts. Also I think your mash time needs to be extended?

make sure you have a good mash tun and make sure you take into account the temp absorption that your tun is going to take out of your mash water. i have taken heating my mash tun to the approximate temp by putting hot water in it. this will help with temp control. my tun drops 1 or 2 degrees over an hour.

oh, and you probably do have ok abv - off the top of my head, probably 4.5% or so
No, you just mash wheat malt just like any other malt.
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