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Dead Ringer All Grain Stuck Fermentation

I brewed the DR all grain (my first) on 4/5 and wound up with an O.G. of 1.070 which was a tad higher than the target 1.065 but not too far off. So I pitched the US 05 when the wort got to 68 capped it and put it in my beer closet. All was good for 4 days and then the krausen fell and all visible activity stopped I waited 10 days and tested the gravity and it was at 1.022 so I gently swirled the carboy to rouse the yeast and left it alone until Saturday 4/26 a full three weeks after brewing. I tested it and got an S.G. of 1.020, I tested again today 4/28 and its still at 1.020.

I’m wondering if the yeast is done and my higher then expected F.G. is due to the higher O.G. or should I leave the beer in primary for longer? If anyone rememembers I recently posted about a batch of surly cynic that I had to dump due to bottle bombs so this is a sensitive subject for me. Any advice is appreciated.

Also my closet stays between 72-76 degrees I know its on the warm side but its the best I can do for now.

what yeast did you pitch? did you make a starter?

how long did you mash? at what temp?

Sounds like it’s done fermenting.

edit: Sorry I see you pitched 05. Seems like it would have attenuated more. From what I understand if you mashed at a higher temp you may have created a less fermentable wort.

I agree with the mash temp being the likely culprit. A ferm temp of mid 70’s is going to send the yeast into overdrive and really attenuate the beer.

What are you using to measure mash temps?

The mash temp started out at 158 ( I over shot the strike water) but I added about 3 quarts of cold water and dropped it to 154 pretty quickly and it stayed between 154-152 for the hour of the mash. I then raised it to 170 for ten minutes. Additionally I did a BIAB so I used 3.5 gallons of sparge water heated to 165 for my sparge temp.

I just kegged essentially the same recipe. 10 lbs 2 row, 1 lb crystal 40, 62IBU of centennial hops,

I BIAB, I don’t do a mash out but I also sparge. I mashed at 151. WY1272 took it from 1.061 to 1.011.

Mashing at 154 would make a slightly less fermentable wort but Loopie may be on to something questioning your thermometer. You also want to make sure you stir the mash well when adjusting temps and check the temp in multiple locations/depths of the mash because there could be hot spots. Especially with BIAB where you may have some pockets of hot liquid outside the bag itself.

I stopped doing a mashout on BIAB because it’s so difficult to make sure you have a consistent temp throughout the kettle and under/around the bag. Besides other more experienced brewers told me it’s not necessary. So I just lift the bag, let it drain, squeeze it a bit and sparge with 190ish water to compensate for the heat loss.

Use whatever method you feel works for you but I think you’re mash temp is the culprit in the higher gravity readings. I’m sure the beer will still be really good. It will just be a little more malty and fuller bodied. Report back on it and let us know.

It sounds really likely that it was mash temps. Once you add the grains to water they start creating their enzymes. So even though you got the mash down relatively quick it was already creating alpha enzymes thus a beer with more body and a wort with less fermentables. In addition a mash temp of 154° is going to favor more alpha enzymes.

Thanks for the replies and advice! Next time I will shoot for 152 for my mash temp. Dannyboy I think I will also try skipping the mash out next time and sparge with hotter water to compensate. All in all I think it’ll be a good product for my first all grain attempt.

One thing I noticed when I transfered to secondary was that I had a massive amount of yeast/trub in the bottom and probably lost a half gallon compared to what I normally transfer to a secondary vessel. Is this normal with an all grain brew? Should I shoot for a bigger boil volume to compensate?

Trub often depends on the recipe. In hop forward recipes you will get more trub. Personally you can create your recipes around such. Already formulated recipes are just that and by boiling more to get more you are essentially changing the recipe (ie OG IBU).

Of course adding things to a beer can cause it to attenuate further - but it may change your expected flavor profile. Re-yeasting with more aggressive yeast may take it further. For example, Brettanomyces would chew it down further, but may give you some unwanted “funk” if you don’t drink it quickly after the expected FG is reached.

I didn’t see this in the other posts so I’ll put it out there. You should double check the calibration of your thermometer, and your hydrometer. A thermometer that is off 2-4 degrees will give you fermentability issues. Test your hydrometer in tap water and it should read 1.000 ( mine is 2 points off so I subtract 2 for all readings). :cheers:

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