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Runyanka

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Last Saturday night I brewed a Youngs Double Chocolate Stout Clone and come Sunday morning my airlock was going crazy. Well Monday came and there was no visable airlock activity. So I let it set until today, where I cracked open the lid, stole some brew and took a hydrometer reading. The reading was 1.021 after almost a week :confused:. What I gently stirred the beer with a sterilized spoon and am hoping for the best. Its suppose to ferment down to around 1.010 and i feel it is no where near close. What should I do? Go to the LHBS and pick up some more nottingham ale yeast and repitch? I had it in a tub of water at around 68 degrees the entire process, so I dont thing it was to cold. I took it out the water and have it just sitting out in open air now, which is at 73.

Any help would put my mind to ease. Thanks guys!!!
 

chilly460

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I hope you don't mind, but I have the exact same issue. I did a Austin Homebrew Samuel Smith Oatmeal Stout clone on Saturday. 1.050 OG, was bubbling away fine after 6hrs or so, and stopped sometime MOnday, sitting at 1.020 now. 68*+ the entire time. Just looking for direction as to next steps, don't want to just start throwing yeast at it.
 
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Runyanka

Runyanka

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Mine was an Austin Homebrew Kit as well.
 

boo boo

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Even using dry yeast, you should aerate your wort well. Adding more yeast now won't help. Underattenuation can be caused by a lot of unfermentables in the extract itself, something you can't control when using extract. Leave it for a few more days and take another reading. If is the same, I would call it done. That said leaving it for a few weeks more wouldn't hurt.
 

talenos

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I started this exact same thread about a week ago. I got a lot of replies saying, do not rely on the airlock. Since you're gravities are going down you're fermenting, so all is good.

Unfortunately for me, mine appeared to have stopped at 1.020, but I learned a lot of stuff since then, and realized I didn't aerate let alone stir my wort, so that may have been it.
 
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Runyanka

Runyanka

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I aireated the crap out of mine after transfering into the primary using and aireation stone. It was going like crazy for about a day and a half. I am just stumped as to why it is stuck. I brewed a hefe the same day and it is already down to 1.012 and still going, and I followed the exact same steps with both.
 

steelerguy

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There were probably just a lot of unfermentable sugars in the extract. 1.020 really isn't all that bad for a stout. Maybe a little more chewy than you wanted, but not bad. Give it a couple days, if it hasn't changed your beer is done fermenting. It is a stout, it will be good! :)
 

chilly460

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So, we should just let it go at 1.020 and not try to restart fermentation? Should I try stirring the wort?
 

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Don't stir it up. You don't want to oxygenate it now.

You can try gently swirling the fermenter a bit, just to encourage the yeast to finish up if they quit early. An oatmeal stout is ok to finish up at 1.020, as long as it's definitely done. If it's still 1.020 after another week or two, then it's fine to bottle.
 

nostalgia

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My AHS coffee malt stout stuck around 1.024. I tried re-pitching US-05 and it did nothing.

I stuck it in the keg and forgot about it for a few months. When I finally carbed and tapped it it was awesome :)

I'm pretty sure my problem was overheating the partial mash and generating unfermentable sugars. It did seem to dry out in the keg, though.

-Joe
 

chilly460

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OK, I'll let it go, no problem. I was going to leave it in the primary for three weeks anyway, so there's no rush. Appreciate the advice. I think the issue was that I may not have oxygenated as well as necessary, I had two batches going and didn't really get it shaken as well as I should have. Live and learn.
 

steelerguy

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I think the issue was that I may not have oxygenated as well as necessary, I had two batches going and didn't really get it shaken as well as I should have. Live and learn.
If you didn't oxygenate enough it may not ferment as fast but it should still finish at around the same gravity. The gravity may still be dropping, just not very fast.
 

chilly460

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I've been checking the wort sample I took when brewed, I'll grab a sample from the fermenter today to see if there is a difference for some reason.
 

scinerd3000

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did you make a starter or rehydrate the yeast if dry? I find that makes a HUGE difference
 

7Enigma

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Even using dry yeast, you should aerate your wort well. Adding more yeast now won't help. Underattenuation can be caused by a lot of unfermentables in the extract itself, something you can't control when using extract. Leave it for a few more days and take another reading. If is the same, I would call it done. That said leaving it for a few weeks more wouldn't hurt.
This is a misleading statement. Underaerated wort will not allow the yeast to multiply to the max numbers possible, and the lower numbers can exhaust their nutrients prematurely which can stall a fermentation. Repitching with more yeast can most definitely help to bring a batch to completion. I did just that with my Young's DCS clone from AHS last March (it was my second brew).

Back then Austin was supplying (IMO) crap dry yeast (regular Munton's) which has a relatively high final gravity, and so I had to use a pack of Nottingham from my local brew store to finish it up. Since then they have switched to Nottingham or the lower final gravity Munton's (Gold I believe?) which should not cause any problems.

In case anyone wants to use my hydration procedure for dry yeasts here's what I do to get the highest number of healthy yeast:

Items needed (all preboiled or sanitized):

-glass cup
-water
-fork
-plastic bag
-dry yeast packet


-30min before pitching (still boiling the wort) I take the glass cup and dip it into the wort to get a teaspoon or two of liquid. You won't crack the glass if you do this quickly, but you can also use a sanitized spoon if you are worried. The purpose here is to slowly introduce the yeast to the wort so it can ramp up enzyme production and other proteins tailored towards the wort prior to getting thrown in the fermenter.

-The combination of the bit of boiling wort and water should be ~90-100F (a drop on the inside of the wrist should feel warm). You can adjust this by adding a little bit more of either to bring up or down the temp.

-Cut open the yeast packet and drop it on the surface of the water/wort in the glass cup. Cover loosely with a plastic bag to prevent contamination (I just lay the baggie over the top)

-Let it sit for 10min. Slowly some of the yeast will sink down into the water.

-After 10min take your sanitized fork and whisk the liquid making sure to get all the dry yeast into solution. You should create a nice froth in about a minute of mixing.

-Leave the fork in the cup and cover the yeast back up with the plastic bag and place in a warm dark location. When it's warmer I put it in a kitchen cabinet, while still cold out I'll put it on a cooling burner (ie warm to the touch if you put your palm on the burner, NOT HOT)

-Every 5-10min I'll stir it a bit more but nothing fancy

-When your wort has been chilled and nicely aerated give the glass a final stir to get it into solution (no clumps on the bottom) and pitch the yeast. Swirl the wort to get the yeast evenly mixed in solution.

-About 30min after pitching (I go and clean up then come back) I'll swirl the fermenter again to put the settled yeast back in suspension.

Sounds like a lot of work but it really isn't, and it will give your dry yeast the best chance of transitioning from spore to alcohol producing machine! :mug:
 

ArcaneXor

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Fixing a stuck fermentation 101:

Ground rules:
- Don't rely on your airlock alone as an indicator for fermentation progress, especially if you use a bucket. Your hydrometer is your most reliable tool for this purpose.

- Are you sure the fermentation is stuck? Take hydrometer samples every two-three days for a week and correct for temperature. It's only stuck if your readings don't change for several days and are at least 5 points above your targeted final gravity.

- Be patient - a stuck fermentation is not a time-critical flaw. Just sitting there for a few extra days is not going to hurt your beer. Think before your act, and give your actions plenty of time to show results before deciding to move on to an alternate fix.

Procedure:

- slowly increase the temperature of the fermenter to near the upper range of the yeast's optimal range, and gently agitate the carboy to resuspend the yeast every few hours. Avoid splashing.

- If that doesn't show a drop in gravity after a few days, consider one of the following options:

1.) Dissolve 3 oz of corn or table sugar along with some yeast nutrient in boiling water, cool it down to fermentation temperature and add this mixture *gently* to your fermenter (avoid splashing). Sucrose and dextrose are very easy for yeast to ferment, and adding some along with yeast nutrients can provide the yeast with just enough of a boost to resume fermentation of more complex sugars remaining in your wort.

2.) Pitch more yeast. This is best done with liquid yeast: Make a very large (half a gallon or more), very well-aerated starter with ample yeast nutrients, let it ferment to completion, decant the starter beer and gently add the slurry to the fermenter. If you want, you can add a second, much smaller starter (1 pint or so) and pitch it at peak activity (along with the starter beer) - that way, you provide a large volume of healthy inactive yeast along with a smaller volume of active yeast. DO NOT aerate or oxygenate your beer when pitching more yeast - that's why we made the large, well-aerated starter.

- If neither of these options works, it's time to consider more drastic options:

1.) Just call the beer done and see how it'll turn out after some aging. It may be fine, or it may need to be blended with another beer. CAUTION: Keg beers that finished significantly high. If you must bottle, use PET bottles. I do not recommend glass bottles due to the increased risk of dangerous bottle bombs. If glass bottles are your only option, be conservative when adding priming sugar, place your bottles in a "bomb shelter" - a sturdy container that can withstand exploding bottles and keep the resulting mess contained, and monitor your bottles for signs of overcarbonation. Use caution when handling potentially overcarbonated bottles - use eye protection, sturdy gloves and cover as much of your body as possible in thick clothing to protect yourself in case a bottle decides to blow up in your face.

2.) Consider pitching a highly attenuative, highly alcohol-tolerant yeast strain such as a champagne yeast if adding more beer yeast did not do the trick. Follow the starter/rehydration guidelines above.

Preventing stuck fermentations in the future:

- Always rehydrate dry yeast in warm water, ideally with a proper dose of Go-Ferm rehydration nutrient. Do not add sugars (including malt extract) or regular yeast nutrient/energizer while rehydrating yeast!

- If using liquid yeast, make a starter, no matter what the directions on the vial/smack pack say. Refer to the Mr Malty Pitching Rate Calculator to see how large a starter you need. Rarely is a starter less than 1.5 qts sufficient to achieve significant yeast propagation. You don't need a stirplate or borosilicate flask - a simple one-gallon glass jug will do just fine (available from most grocery stores filled with apple juice). Shaking it up every hour or so will provide the yeast with plenty of oxygen to grow.

- Know your water chemistry. Yeast needs calcium to be happy. If your water has less than 50 ppm calcium, add some, but don't exceed 150 ppm (this is less critical for extract brewers, since the extract itself contains minerals).

- Temperature control is hugely important. Use a dedicated chest freezer or fridge with external temperature controller, a swamp cooler (the "wet t-shirt method", or - as I do - a picnic cooler:



Monitor temperatures closely and avoid swings of more than 2 degrees. Here is the important part: As fermentation winds down, allow the temperature to slowly rise to the upper range of the yeast's optimum (usually the low to mid-70s for ale yeasts). This will result in higher attenuation and less chances of premature flocculation, as well as more rapid reprocessing of undesirable fermentation by-products. Some highly flocculant yeasts may need to be resuspended by agitating the carboy occassionally. Because this temperature increase is done slowly and when fermentation is almost complete, no excessive esters, phenols or high alcohols will be produced.

- Use yeast nutrients. While beer wort contains nearly every nutrient that yeast need to prosper, but it can be short on zinc, and some nutrients are not very readily available. Providing external nutrients (usually added late in the boil, occasionally during fermentation) costs only a few cents per batch and is just one more tool to maximize yeast propagation, vitality and viability.


Summary:

With adequate temperature control, water chemistry (especially calcium), proper yeast rehydration (or a large starter if using liquid yeast) and proper supply of labile yeast nutrients, it's almost impossible to get a stuck fermentation. Preventing one is much easier than fixing one.
 

7Enigma

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I'll take #2 any day of the week if I have a stuck fermentation. There is no better single sure-fire way of fermenting than adding addtional yeast (be it liquid or dry). You can guess on yeast nutrient, temperature issues, etc. but you can be sure adding additional yeast WILL produce more alcohol (as long as the ABV isn't above the tolerance of that particular yeast). The less times I remove the airlock the less chances for contamination, so I only want to do it once. I use dry yeast exclusively and so an extra $1-2 is insignificant, but some of the more expensive liquid yeasts it's your choice whether you want to.

I also don't agree with this:

Always rehydrate dry yeast in warm water, ideally with a proper dose of Go-Ferm rehydration nutrient. Do not add sugars (including malt extract) or regular yeast nutrient/energizer while rehydrating yeast!
I agree you shouldn't just dump the yeast into the wort, but a low concentration in the hydration water gives the yeast additional time to ramp up metabolism. In my yeast hydration description I do recommend allowing the yeast to rest for 10min before actively mixing but think having the yeast in no contact with fermentables is not a good idea.
 

davesrose

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In my yeast hydration description I do recommend allowing the yeast to rest for 10min before actively mixing but think having the yeast in no contact with fermentables is not a good idea.
I've also found I like having dry yeast all ready and conditioned well before pitching. I actually put a pack in a cup of sterilized water with DME hours before to create a mini-starter.

As for the OP....what was your original gravity reading? As has been mentioned, stouts can have a higher final gravity since they are more forgiving for "malty" profiles. If you have a very high original gravity, then you need more yeast cells that are found in one pack. If your original gravity was 1.05 or so, then it probably has to do with one of your methods: making the dry yeast viable and making sure you have aerated the wort well enough. Worst comes to worst, you can taste the beer now. If it's great, why mess with success (and a lower ABV beer...you can drink more of it!!). Leave it alone and bottle it after 3 weeks from brew day. If it is too malty, try the above methods for repitching yeast.
 

ArcaneXor

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I've also found I like having dry yeast all ready and conditioned well before pitching. I actually put a pack in a cup of sterilized water with DME hours before to create a mini-starter.
From what I have read, doing this isn't particularly healthy for the yeast because the cell membranes cannot control what passes through them until they are all the way reconstituted, i.e. osmotic stress can result. Palmer tends to agree with me on that (How To Brew, 3rd edition, pp 72-73). But if it works for you, great - in most aspects of brewing there are many, sometimes seemingly contradictory ways to get great results!
 

davesrose

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But if it works for you, great - in most aspects of brewing there are many, sometimes seemingly contradictory ways to get great results!
+1! I've found I get good cell count with going ahead with rehydrating and adding DME at the same time (these yeast samples are pretty well modified to begin with), but that's my way. It's like proofing active yeast for bread: I like to add my teaspoon of sugar in warm water before I add the yeast: other people swear by leaving the sugar out. Either method should give you healthy yeast....whatever way works for you
 

7Enigma

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Yeah, not sure about hours before pitching, but I would wager that method is better than sprinkling the dry yeast directly on the wort as many people do. The concern with such a long period of time between hydrating and pitching is the danger of exhausting the oxygen supply in the cup causing the yeast to transition early to anaerobic metabolism. This can lower the total number of yeast cells as aerobic metabolism is much more energy efficient than fermentation and so the yeast are likely not multiplying to the same degree.

I would recommend if you are going to use a couple hours I would hydrate them up in a very weak DME solution (or water an then in a 10-20minutes add some DME), and then in another hour or two add some more. And use a filtered air stone to supply oxygen.

There is a real risk to having too much malt present during hydration (as ArcaneXor mentioned), but if you start out with a low concentration and then increase, I'm sure it's good.
 

davesrose

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Yeah, not sure about hours before pitching, but I would wager that method is better than sprinkling the dry yeast directly on the wort as many people do. The concern with such a long period of time between hydrating and pitching is the danger of exhausting the oxygen supply in the cup causing the yeast to transition early to anaerobic metabolism. This can lower the total number of yeast cells as aerobic metabolism is much more energy efficient than fermentation and so the yeast are likely not multiplying to the same degree.
Well then why do we make starters? While we are talking about a weaker concentration of malt then in wort, I'm not sure the concern about what type of metabolism is going on....the idea for a starter is to multiply the cell count of yeast: not be concerned what stage of metabolism each cell is at. Some yeast will have gone through metabolism and would be going dormant, while others will be active. But during the period of metabolism, they would have multiplied. Then when you pitch to aerated wort, it's a whole new feeding schedule for them.

As I see it, this is just like proofing bread yeast. Some people swear by putting that sugar in, others say it's bad. At least I like to put that teaspoon of sugar in with the bread yeast as I believe having some food helps yeasts feed and begin to get active. No right or wrong. I understand the other arguments for only hydrating...and there's validity in that as well. I'm just saying my pitch count seems good if I do add DME with the yeast in a period long enough to be considered a starter (my pitch rate is definitely better then just hydrating). My beer also seems to begin to ferment and attenuate like starters I make with liquid yeast as well.
 

7Enigma

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Well then why do we make starters?
Starters are made to increase the total yeast cell count, and this is done primarily under oxygenated and stirred conditions. When you just add the yeast to some sugar water or diluted wort and let it sit for hours you are really not creating a yeast starter, or at least in the traditional sense. Add a stir plate and a filtered airstone and now you're talking about an effective starter.
 

davesrose

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Add a stir plate and a filtered airstone and now you're talking about an effective starter.
Yes, you can get a higher cell count if you have a sample that's continually aerated....but we don't have stirplates in our fermentors and they seem to turn out well. I'm not arguing that if you keep aerobic metabolism going, you get an even higher cell count....but you don't get a decrease of cells with traditional fermentation (you get more, just not as much as with a stir plate). A small difference, yes...but one that explains why one can get good attenuation with just aerating the wort before pitching. Anyway, our arguments...while a good debate...I think are getting offtrack of the OP
 

RedIrocZ-28

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Interesting that no one mentioned the 1.020 stuck fermentation curse. Or that there have been lots of reports of Nottingham yeast not fully attenuating.

In your case OP, I would repitch a pack of Safale 05.
 

7Enigma

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Interesting that no one mentioned the 1.020 stuck fermentation curse. Or that there have been lots of reports of Nottingham yeast not fully attenuating.

In your case OP, I would repitch a pack of Safale 05.
Hmm, news to me. I've been away from the forums for a while with other projects and so haven't seen this. Were these reports all from Austin Homebrew or just Nottingham in general? Wondering if it's not just anecdotal, and could be a bad batch of yeast. I think I just used Nottingham in my Ruination IPA...
 

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