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Old 06-20-2011, 02:39 AM   #1
asterix404
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Mar 2009
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So I don't know what I did wrong if anything or if I have to give it more time. I made a stout using this recipe:

7lb pale 2 row
3lb oat malt
1lb black patent
2lb flaked barley
2lb roasted barley

I hit a mash temp of 152, it dropped to 150 in 90min. I sparged to hit 168. OG was 70GP.

I pitched 2 packets of American dried ale yeast from saflage (I think s-04?) the very typical clean, high attenuation yeast.

I check 16 days later to rack it and I only have an FG of 32 with no action from the air lock, no kaursen, very little bubbling in the liquid etc. I racked it anyway because I needed the bucket but this is very strange. It fermented hard for about 4 days so I figured it was very close to done... but 32 is no where close to where it should be. A calculator tells me about 19. I am going to let it sit in the secondary for about 3 or 4 weeks but I was just wondering if I did something wrong.

 
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Old 06-20-2011, 03:06 AM   #2
djsethall
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It's the oat malt. What software did you use to calculate gravities?

 
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Old 06-20-2011, 11:47 AM   #3
Rondacker
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I'm interested to see the answers to this one;
I'm having the same situation with a Wit.
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Old 06-20-2011, 12:43 PM   #4
asterix404
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Mar 2009
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I used http://www.brewersfriend.com/allgrain-ogfg/

I mean, even with the 3 pounds of oat malt it only added about 10GP. Does it really impart nothing fermentable? I actually don't mind this, I was hoping to get a lighter gravity Dry Irish Oat stout but an 11GP difference sort of shocked me. When I brew with oats, do I need to mash at a much lower temp? Like in the 147-149 range?

 
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Old 06-20-2011, 06:22 PM   #5
dcp27
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oat malt is most certainly fermentable and it can be used 100%. black patent and roasted barley on the other hand are barely fermentable. you got too much specialty malt in this and may just stretched the enzymes too thin. try adding 1 tbs of amylase enzyme, most LHBS will carry it.

 
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Old 06-20-2011, 06:25 PM   #6
jsweet
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Apr 2011
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Did you taste it? If it doesn't taste overly sweet, maybe that is your FG. If it does taste too sweet, maybe you have a stuck fermentation.

 
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Old 06-20-2011, 06:53 PM   #7
asterix404
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I am skeptical that I stretched the enzymes too thin, but that might be true. I have done even heavier recipes than this but with more base malt. I wouldn't have thought that about 20% of no enzyme specialty mash would have broken it. I mean, the recipe was 15lb, only 3 was chocolate and dark. I do wonder if you are right, but I needed to treat Oat Malt not as a base.

I know I don't have a stuck fermentation, I pitched 2 packets of dry yeast and it went mad for about 3 or 4 days. I did a beer much like this one, but without the oats and I hit about 15GP. I did not try it, but I am thinking I am going to this weekend. Even if it is sweet, it could also mean that the enzymes during the mash didn't convert the starch correctly.

If the FG doesn't go down in the secondary between now and this weekend I will get some of the enzymes and pitch them and wait another 2 weeks or so. Will they still work if the ambient temp is about 75? I just watched a video that told me they work really well between 130-150.

 
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Old 06-20-2011, 08:02 PM   #8
dcp27
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well oat malt can actually be treated as a base malt as it has enough diastatic power to convert itself and once upon a time was used in large proportions of the grist. in hindsight, i think i was wrong about the enzymes being stretched too thin. any chance your thermometer is off?

if you add the AE, while it does work best in that region, you're obviously going to kill your yeast if you heat it up that high. it still works at room temp, its just a bit slower. and dont worry about any fears of it ruining your beer, only beano will do that. heres a post about a similar problem: http://www.homebrewtalk.com/f163/esc...rescue-212926/

 
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Old 06-20-2011, 08:26 PM   #9
asterix404
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That is very strange, I mashed at 152 and down to 150. My thermometer and hydrometer are fine. I will add the enzymes this weekend I think. This has just never happened to me before. This seems to be a very good idea to have on hand for just these sorts of bizzar problems even when everything is done right.

 
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Old 06-27-2011, 12:22 PM   #10
asterix404
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So after thinking about it, it's possible that I was really stupid and did something different with the MLT with this particular brew, and only this particular brew which could have dropped the temp to below 145. I basically forgot to put the comforter around it, but I did have 2 or 3 fleece blankets. Anyway, I added the enzymes and 3 or 4 days later there is a nice head forming in the secondary. I will give this two weeks or so and I think bottle. Thanks all!

 
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