Fermentation temps

[f0xtr0t]

I am using a recipe for Chocolate Orange Holiday ale from Austin home brewing. I have a very slow or maybe stuck fermentation. It uses WL011 European ale yeast.
I have had some issues with this batch.
First off I used 6th month old yeast. The best by date was December on my vial. White labs says the best by is 4 months.
I made a 3 quart starter with 1/2 cup of LME then let run for 8 hours. I pitched this with no signs of fermentation. I aerated very well. I had no activity for 24 hours then I aerated again very well. Then about 2 hours after aerating the batch was vigorously fermenting for about 36 hours at 78 degrees. Until I read that the WL011 ferments at 65-70 degrees. I made a cold water bath and cooled to about 65. The activity stopped. I let it warm up to 70 but it is still not bubbling.
The instructions say to let yeast warm up to 72-78 and pitch.
I'm just not sure what to do now. Is this a wait and see thing?

 

[madchemist83]

I had similar problem. I added yeast while wort wad still hot and it only fermented for about a day or two. Wait for your fermentation to stop completely. Then transfer into secondary. Let it sit for about 12 hours. Add amylase enzyme,mix well but don't aerate, then add more yeast.

 

[Hang Glider]

Next batch, get your temps under control. The yeast's metabolic activity will raise the temp of your wort from 5-10F easily. Many of us here get the wort to about 62-65, then pitch, and hold the temps steady. (my preferred is 63F, water bath)

You can dedicate a refrigerator to the task with a temperature control device to regulate the compressor, or you can set the fermenter in a tub of water and use an aquarium heater or a few frozen water bottles to regulate the temps... as fancy or as simple as you want.

Even though I'm fermenting at the bottom of the range, I use a blow-off tube the first week or so, as my yeast get very happy.

Good for you making a starter with an older yeast (or any liquid yeast), but next time go for 24-36 hours prior to pitching. My starters rarely show any signs of activity, but there's a lot more yeast in the bottom than what I put in!

For now, I would let it sit - since you had activity, you have viable yeast (although you may have some off flavors due to the extra heat). Let it sit 2-3 weeks without touching it, but keep it in the mid 60s if you can. Pay no attention to if the airlock is bubbling or not - that's just gas escaping and not a reliable indicator of actual yeast activity. In three weeks, take a hydrometer reading and see where you're at.

 

[madchemist83]

I wouldn't recommend keeping it on yeast cakr for longer then two weeks. Rack it into secondary. Also im pretty sure CO2 is very good indicator of yeast activity. So if it doesn't bubble it's done fermenting.

 

[Hang Glider]

...Also im pretty sure CO2 is very good indicator of yeast activity. So if it doesn't bubble it's done fermenting.

or.....
you don't have a good seal and gas is escaping elsewhere. Hydrometer is a much better instrument to determine completion than watching bubbles.

 

[madchemist83]

True. I was hoping op got sealed system.

 

[BamaRooster]

You really need a hydrometer reading to tell where it is in the process. It is possible it is done. AIR LOCKS ARE NOT AN INDICATION OF FERMENTATION, THEY ARE AN INDICATION THAT THE PRESSURE IN THE VESSEL IS GREATER THAN THE PRESSURE IN ITS ENVIRONMENT. This may or may not be because of active fermentation. And the lack of air lock activity is a indicator of nothing other than no gas is being released through the airlock. It really is as simple as that. listen to Hang glider he is giving good advice.

 

[TopherM]

I wouldn't recommend keeping it on yeast cakr for longer then two weeks. Rack it into secondary. Also im pretty sure CO2 is very good indicator of yeast activity. So if it doesn't bubble it's done fermenting.

Yeah, don't listen to this guy (no offence, madchemist, you just have very outdated info....). He's regurgitating info from a book from the 80s or something his LHBS told him.

Yeast autolysis only takes place at significant pressures, like those found in a commercial brewery. You can leave your beer in primary almost indefinitely without issue. The latest guideline is about THREE weeks for full attenuation and yeast cleanup of byproducts for average gravity wort.

Second, the airlock is NOT the primary judge of active fermentation. Fermenters are not vacuums, and CO2 or any other liquid or gas will always take the path of least resistance once they fill the headspace. Sometimes that's the airlock, sometimes it's not. Lots of variables involved that you can't control.

The only primary sign of fermentation is solution gravity, so it's not done until your hydrometer says it's done. Again, as long as you are fermenting an average gravity wort (under 1.07 or so OG), three weeks will complete the fermentation. Higher gravities, insert a little more time.

 

[madchemist83]

Ok just to be clear. Yeast eats sugar to produce alcohol, CO2 and other byproducts. CO2 will eventually build up and airlock will release extra pressure. Therefore bubbles indicate fermentation activity. Now how often that will happen is another question. Remember that there is dissolved gas in ur beer and sediment which will cause wrong hydrometer readings.

 

[Hang Glider]

Remember that there is dissolved gas in ur beer and sediment which will cause wrong hydrometer readings.

very good point - clean clear samples (no trub!), tap any bubbles loose, spin the hydrometer in the test jar....then take the reading.

 

[f0xtr0t]

Ok how do you account for the sediment and co2 in the wort? Or is the only way to use a refractometer to get a brix measurement?

I want I know if I could have cold shock killed the yeast. I dropped 15 degrees from 78 pretty quick. I've just never heard of that before. Before the ice bath I had a very vigorous ferment going then nothing once it cooled.

My fermenter is sealed.

 

[JLem]

Ok just to be clear. Yeast eats sugar to produce alcohol, CO2 and other byproducts. CO2 will eventually build up and airlock will release extra pressure. Therefore bubbles indicate fermentation activity. Now how often that will happen is another question. Remember that there is dissolved gas in ur beer and sediment which will cause wrong hydrometer readings.

But if the fermenter is not air-tight, you won't get airlock activity. Also, lack of fermentation does not mean it is "done". It is possible that the yeast dropped out early due to adverse conditions or, like in the OP's situation, a sudden drop in temperature. Only a gravity reading will really tell you what is going on in there.

And non-dissolved sediment in the beer will not impact your hydrometer reading. Hydrometers essentially measure the density of the liquid and density is only affected by what is dissolved in the solution.

Please stop giving wrong advice so cavalierly.

 

[JLem]

Ok how do you account for the sediment and co2 in the wort? Or is the only way to use a refractometer to get a brix measurement?

I want I know if I could have cold shock killed the yeast. I dropped 15 degrees from 78 pretty quick. I've just never heard of that before. Before the ice bath I had a very vigorous ferment going then nothing once it cooled.

My fermenter is sealed.

No need to account for sediment. Just make sure there are minimal bubbles sticking to the hydrometer by giving it a good spin.

It is possible that you shocked your yeast, but only a gravity reading will tell you for sure.

 

[PVH]

It is possible that you shocked your yeast, but only a gravity reading will tell you for sure.

Yeah - 78F to 65F is a hell of a swing and could definitely shock the yeast. Also, it is possible that you're near FG. I see on the AHS site that your OG for that kit is 1.052. 36 hours at 78F could get you pretty close to the 1.016 expected FG. Note that the 36 hours is from fermentation beginning, not from pitching.

 

[TopherM]

I'm done arguing, but just FYI to the OP, there is a LOT of misinformation and bad advise in this thread, IMHO.

I urge you to do your own research so you can pick out what's good info and what's bad info. Instead of following the conflicting advise in this particular post, do a forum search of yeast autolysis, airlock activity/active fermentation, fermentation temps, etc. Read 3-4 threads on each keyword then make your own evaluation on what to do.

When in doubt, I follow the advise of the longest tenured HBT member. If one of the moderators posts advise, always listen, they know their stuff. If someone with under 100 posts gives advise, take it with a grain of salt, they are typically quoting something they read or heard.

Good luck!

 

[Hang Glider]

Ok how do you account for the sediment and co2 in the wort? Or is the only way to use a refractometer to get a brix measurement?

I want I know if I could have cold shock killed the yeast. I dropped 15 degrees from 78 pretty quick. I've just never heard of that before. Before the ice bath I had a very vigorous ferment going then nothing once it cooled.

My fermenter is sealed.

okay - there are no necessary adjustments to consider - just draw a clear clean sample, tap the bubbles loose - that will be good enough. Oddly enough, the alcohol present at the end of the fermentation adversely affects refractometer readings moreso than hydrometer - I use my refractometer during boil activity to adjust water, malt, boil off time, as needed, but at the end of the ferment, I trust my hydrometer more.

even though you've seen nothing since it cooled, it may indeed have finished up - You can carefully (cleanly) draw a sample and check it. But it won't hurt to sit another week or two, even if it is done. All my beers sit at 63 for 4 weeks before I do anything at all with them. Perhaps I could do it faster, but as I've moved in this direction, my beers have improved tremendously in quality, so I'm going with what works for me. Temp control, yeast volumes, and time. Good old-fashioned time. oh, yeah, and sanitation. I got careless and had a dumper a couple months ago.

and cold doesn't kill yeast - heat does (okay, freezing isn't good...) but your yeast are just fine. There are plenty still in there, just waiting for your priming sugar so you wont have to do anything special (yeast-wise) when you're ready to bottle.

 

[f0xtr0t]

Ok I managed to take a sample 1.022. I should have just taken a hydrometer reading. I managed to hit the attenuation window in just 3 days. 1.022 is the adjusted number after I added sugars to boost the ABV the original FG was 1.016 but ibrewpal shows with an accurate grain bill 1.022 is the estimated final gravity. The problem was SWMBO set the a/c to 78. I think I may get off flavors/esthers/fusel alcohols but it has been my experience that some aging will mellow every thing out.

I am going to leave it in the primary for 2
more weeks in between 65 and 70. Then off to the keg.

Autostlysis I think happens. I brewed a pumpkin ale last fall. Keg cowboy was 6 weeks late with my kegging supplies. So it sat in my secondary. All I could smell was yeast. After 3 weeks aging in the keg all I could taste was yeast. 3 1/2 months later the flavor mellowed and well I can't describe what type of bear it tastes like. ( I just don't have that much experience) but there was no pumpkin or cinnamon taste at all. So I think Autostlysis can happen in a 6.5 gal Carboy not just a huge conical fermenter. (that beer stayed at proper temps)

 

[Hang Glider]

The problem was SWMBO set the a/c to 78.

that certainly won't help anything. Don't they know we're making beer?? :cross:

ambient temps plus active phase yeast reproduction may have hit as high as 85F

It probably won't be your best beer, but it will be beer, and you've learned some things along the way - heck I learn something every time I brew, so good for you.

 

[BamaRooster]

I wouldn't recommend keeping it on yeast cakr for longer then two weeks. Rack it into secondary. Also im pretty sure CO2 is very good indicator of yeast activity. So if it doesn't bubble it's done fermenting.

OP this is bad info, take it from very experienced brewers, Like REVVY and search this forum as suggested.

 

[madchemist83]

Fair enough. Don't listen to me. I was apparently reading old books. Sorry for misleading posts. I'm currently reading book brewing yeast and fermentation. Nice book.