Strange yeast behavior. Is US-05 getting weird on you?

[Chadwick]

Last three batches I brewed using US-05 has acted strange. My brews are generally pretty high gravity. I've been setting up my blow-offs expecting a violent fermentation. It hasn't happened. Rather, I was wondering if fermentation even started. It has been the same with all three brews. 3 days before I see airlock activity. Once I do see it, it is mild and slow. Activity lasts for about 3 days, very slow activity. Then nothing. Knowing that airlock activity does not equate fermentation activity, I waited two weeks before I opened up things and took a gravity reading.

In every case, the gravity reading showed 90% attenuation.

What is up with this? This is just blowing my mind. My equipment is tight. So is the accuracy of my tools. The only thing I'm doing different from what I have done in the past is that I'm actually pitching 3X as much viable yeast as I have typically done in the past with brews of equal gravity. I expected all hell to break loose. Instead I'm met with very mild fermentations with little CO2 activity. Is this normal? I've been brewing for a while and I've never seen US-05 act like this. Sure, it's a more mild fermenter than some other strains, but this is rediculous.

 

[Chadwick]

I'd like to add, I even used yeast nutrient in these worts. Is that a clue in this mystery? I'm not sure. In the past, the only yeast nutrient I've used was old yeast added to the boil. This stuff was the Wyeast stuff they sell.

 

[Harry482]

What temp are you fermenting at? Winter house temps generaly slow things down.

 

[AndytheBeave]

yep I have seen this as well. I saw this a couple of batches ago on a blonde ale. It took for ever to take off and when it did there wasn't a ton of exciting activity. It did attenuate well though after about 4 days. The only thing I don't really like about this yeast is it doesn't pack into a nice cake like S04 does.

 

[AndytheBeave]

What temp are you fermenting at? Winter house temps generaly slow things down.

true, however contrast that to S04 which takes off like a bat out of hell. Even when pitched dry.

 

[Chadwick]

I actually mixed some S-04 with one of these brews. It was fermented very cool. It was fermented at 65F after being pitched at 62F. Regardless, the fermentation was extremely mild. This wasn't expected because the OG was north of 1.095. I was expecting an explosion. It didn't happen. This was with yeast nutrient applied and extensive oxygen added. It just blows my mind.

 

[day_trippr]

US-05 is my go-to rock.
It never fails when run in its wheel house...

Cheers!

 

[amcclai7]

I've noticed this as well. Slow to start and not a lot of airlock activity. However, its still an amazing yeast. Attenuates really well, clean as hell, and is very forgiving temperature wise. You said you've noticed this for the last 3 batches. Have did you notice any off flavors? If not, then I'd say don't worry about it.

Also, and this is just a theory, think about the yeasts that take off like crazy. In my experience these have been hefe and Belgian strains. What do those have in common? Tons of esters. I think there must be something to having a long lag phase that cuts back on esters.

 

[whitehause]

Same here....use s-05 all the time, this last brew I did it took 2 days to start, never had that happen before.

 

[hopdropper]

I'll chime in too...maybe it's coincidence, maybe not. As I type I'm sipping an IPA I fermented with US-05 in November. It took two days for fermentation to begin, and another 8 for it to complete (at day #9 I still had one bubble per second out of the airlock). I thought I screwed up the batch. It was a slow and steady ferment, temp controlled right at about 65F. The final product is decent...but that was the weirdest fermentation I've experienced. And those yeasties had a healthy wort to swim in too...added nutrient and a 60 second oxygen blast.

 

[Chadwick]

It's comforting to know that others are also experiencing these slow starts with US-05. That tells me that it isn't anything I'm doing and that it is the yeast. So far everything has finished good and attenuation has been as good as ever. No off flavors are occuring so I'm not going to worry about it.

 

[VT-NAV]

In every case, the gravity reading showed 90% attenuation.

It sounds less like you have a US-05 acting weird problem and more of a blowoff / stopper acting weird problem.

Check your seal.

 

[atoughram]

I'm drinking my first batch of a US-05 pale ale and all I can say is WOW! Good stuff... A bit better than WLP-001 - which is what I previously used on this recipe.

 

[cjgenever]

How much are you pitching? Into what vol? Info man, info!

 

[beerenstein]

I did back to back batches last Saturday a week ago. Pitched first (oatmeal stout) with us-04. Pitched 2nd (amber ale) with us-05. Stout with 04 had a thick Krausen forming within 5-6 hours. Amber with 05 took about 3/4 of a day to 24 hours to form a Krausen. Both are still visibly fermenting, if I hold a led flashlight up to the carboy. Also, bubbles are coming from the bottom of the carboys. Idk if this is normal, but I thought ale yeasts were top fermenting? ??

 

[Chadwick]

How much are you pitching? Into what vol? Info man, info!

I'm glad you asked this question because I made it a point to start pitching much larger quantities of yeast than I have in the past.

Both of the brews Im referring to have starting gravities around 1.100 and were given yeast nutrient in the boil as well as oxygen. I made starters for both. One was a pack of US-05 I used to make a starter in 2 liters and then I pitched that starter along with 2 more packets of hydrated US-05. The second one was almost the same thing repeated, the starter was US-05 and then a pack of hydrated US-5 and hydrated S-04 was pitched along with it.

 

[amcclai7]

I'm glad you asked this question because I made it a point to start pitching much larger quantities of yeast than I have in the past.

Both of the brews Im referring to have starting gravities around 1.100 and were given yeast nutrient in the boil as well as oxygen. I made starters for both. One was a pack of US-05 I used to make a starter in 2 liters and then I pitched that starter along with 2 more packets of hydrated US-05. The second one was almost the same thing repeated, the starter was US-05 and then a pack of hydrated US-5 and hydrated S-04 was pitched along with it.

I have heard from dozens of people more knowledgeable than me(both on this forum and pretty much every beer book or online article I've ever read) that you should not make a starter with dried yeast. not only is it unnecessary, it could actually harm the yeast. Perhaps this is the reason, along with the US-05, why your ferms have been so slow to take off.

 

[joshesmusica]

I actually mixed some S-04 with one of these brews. It was fermented very cool. It was fermented at 65F after being pitched at 62F. Regardless, the fermentation was extremely mild. This wasn't expected because the OG was north of 1.095. I was expecting an explosion. It didn't happen. This was with yeast nutrient applied and extensive oxygen added. It just blows my mind.

lower temps for us-05 are good, but it will likely be a bit slower. have you pitched in similar weight wort with similar pitching rates and similar temps before and seen this strain take off?

i am under the impression as well that there is no need to make a starter for a dry yeast. simply rehydrating should do the trick. (10ml per 1 gram of yeast at 80F)

I've noticed this as well. Slow to start and not a lot of airlock activity. However, its still an amazing yeast. Attenuates really well, clean as hell, and is very forgiving temperature wise. You said you've noticed this for the last 3 batches. Have did you notice any off flavors? If not, then I'd say don't worry about it.

Also, and this is just a theory, think about the yeasts that take off like crazy. In my experience these have been hefe and Belgian strains. What do those have in common? Tons of esters. I think there must be something to having a long lag phase that cuts back on esters.

actually a long lag phase will add to the amount of total diacetyl produced, and therefore total amount of diacetyl left over after the yeast do some clean up.

http://www.howtobrew.com/section4/chapter21-2.html

what affects those types (hefes and belgians) of strains, and the esters produced, isn't the lag time, but the temp in which they're suggested to ferment at.

In every case, the gravity reading showed 90% attenuation.

is this 90% of what you expected it to attenuate to? or is it apparent attenuation?
are you saying that you started at 1.100 and got down to 1.010? or are you saying you expected it to, for example, get down to 1.012 and it got down to 1.020?
fermentis expects an average apparent attenuation of 81%. this would mean that if you started at 1.100 you should expect an FG of about 1.018. so if you got 90% apparent attenuation, then you're doing great! (that is, if you wanted it that dry) but if you mean you got 90% of that expected 81% (and therefore an FG of 1.026), then yes, there's possibly something wrong.

BUT that doesn't mean that the yeast is the problem. could just mean too many complex sugars that the yeast couldn't break down.

what styles are we talking here? maybe it's not bad if they're a bit sweet?

 

[joshesmusica]

the only time i've experienced longer than normal lag times (longer than 24 hours) with us-05 was on my last brew with it. i was pitching some harvested yeast (second time to use it) into half of my wort with ambient temp around 64. i do this from a technique i read about and wanted to try out in order to avoid a starter. with this method before i've been able to pour in the second half of my wort at the 24 hour mark, but with this one i had to wait until about the 36 hour mark.

 

[A2HB]

I have a beer that's been brewing with two packets of US-05 for 10 days now and it hasn't stopping putting out the bubbles. The first time I used that yeast all bubbling was finished by day 7 so I'm not sure why there is still activity going on. O.G. was only 1.056 but I did add a bunch of turbinado sugar to the boil so maybe that's what's causing this? I want to rack to secondary for dry hopping but it's still bubbling so obviously not done fermenting yet. It seems like it's taking too long for some reason, am I just being apprehensive or should it be done by now?

 

[Hello]

I noticed that my last batch with US-05, a SMaSH took a bit but it was on the cooler side when I pitched and it didn't get back to mid 60's for a good day. I had also wondered about it because I recalled US-05 being super quick. I got good attenuation as well, but I felt like it was slow and didn't flocculate as quickly as it normally does.

 

[amcclai7]

I have a beer that's been brewing with two packets of US-05 for 10 days now and it hasn't stopping putting out the bubbles. The first time I used that yeast all bubbling was finished by day 7 so I'm not sure why there is still activity going on. O.G. was only 1.056 but I did add a bunch of turbinado sugar to the boil so maybe that's what's causing this? I want to rack to secondary for dry hopping but it's still bubbling so obviously not done fermenting yet. It seems like it's taking too long for some reason, am I just being apprehensive or should it be done by now?

I've had long slow ferments with this yeast and never had a problem with the finished product.

 

[edroberts]

From what I've heard, starters aren't necessarily a bad thing with dry yeast. It's just often easier and cheaper to simply buy another packet.

Either way, it certainly appears like this is not an isolated case with US-05. I wonder if there are some generational affects that are manifesting themselves in that yeast from the manufacturer.

 

[joshesmusica]

I have a beer that's been brewing with two packets of US-05 for 10 days now and it hasn't stopping putting out the bubbles. The first time I used that yeast all bubbling was finished by day 7 so I'm not sure why there is still activity going on. O.G. was only 1.056 but I did add a bunch of turbinado sugar to the boil so maybe that's what's causing this? I want to rack to secondary for dry hopping but it's still bubbling so obviously not done fermenting yet. It seems like it's taking too long for some reason, am I just being apprehensive or should it be done by now?

bubbling is not a sign of fermentation. it's a sign of gases releasing out of your airlock, and nothing more. the only way to tell if your fermentation is done is by checking the gravity. if it's hit the same FG 3 days apart (measure one day, skip one day, measure again), then you're done fermenting and can move to a secondary.

for example. i just dry hopped a beer that had been fermenting for 10 days. (i don't do secondary, but that's for another thread). brought it into a warmer room. check the OG (hit my FG), then threw in the dry hops. that was 2 days ago, and you know what? as i typed this i just heard bubbling through the airlock.

to the OP. do this exact same brew in 5 months from now with this exact same method, but when the ambient temps are likely to be warmer. it will be a fun experiment to see if it's the temps causing the slowness.

 

[stonecutter2]

Just brewed an APA with US05 without any weirdness. Chugged along as expected, and started within 24 hours. Wouldn't say it was a super vigorous fermentation, but it seemed just fine.

 

[SC_Ryan]

I'm glad you asked this question because I made it a point to start pitching much larger quantities of yeast than I have in the past.

Both of the brews Im referring to have starting gravities around 1.100 and were given yeast nutrient in the boil as well as oxygen. I made starters for both. One was a pack of US-05 I used to make a starter in 2 liters and then I pitched that starter along with 2 more packets of hydrated US-05. The second one was almost the same thing repeated, the starter was US-05 and then a pack of hydrated US-5 and hydrated S-04 was pitched along with it.

This is massively over-pitching. Two re-hydrated packets are enough to ferment 5 gallons of 1.110 wort. Might have something to do with the extended lag.

 

[Chadwick]

I can't see how over-pitching yeast could have a negative effect on the beer. I wanted to pitch huge amounts with familiar recipes so that I can judge the difference, if any, a larger pitching of yeast may incure.

Someone asked about attenuation earlier. My attenuation is 90% apparent attenuation. So yeah, I did have a FG of 0.010 with an OG of 1.100. I was really amazed by that. Of course, I allowed the temps to rise to about 72-73F the second week in the primary.

 

[olotti]

I've used 05 many times before but sat I used one packet in a smash ipa and i didn't take into account the cooling of the glass carboy while outside and after pitching my fermometer read 58 deg. After placing in the basement the temp slowly rose and it started to bubble but almost 4 days later the krausen never got higher than an inch and it was just a slow steady bubbling never any real furious carboy activity then slowing. Maybe the cooler temps slowed it down but it fermented in the 63-65 range so I'm surprised once it got going it didn't speed up a little.

 

[amcclai7]

I can't see how over-pitching yeast could have a negative effect on the beer.

http://sciencebrewer.com/2012/03/02/pitching-rate-experiment-part-deux-results/

Check out this, or many other links on the subject.

Here's a quote from the article (experiment was to take the same wort, a Belgian ale, and split into 3 carboys, one underpitched, one standard, and one overpitched)

"The under-pitched was fuller on the palate and contained more fruity esters that reminded me apples, pears, and some peach. The overpitch beer was clearly thinner bodied and scrubbed of many flavors. It just seemed duller. The control brew had some spicy phenolics going on and the pilsner malt really shined through."

EDIT: I actually posted that article before I read all of it. Wow! its really, really worth a read. Here's another quote that shows why overpitching can be detrimental.

"My gut feeling is that for a wort of average strength, you could cut the pitch rate from 30 – 50% and still achieve or exceed final attenuation vs a control. You’d have higher esters, but a revitalized (younger) yeast set afterwards. We will sometimes slightly underpitch when we want to put some more vigor back in a culture that otherwise seems healthy. Conversely, overpitching ages the culture – fewer daughters, over time, leaves you with a lot of battle-weary scarred cells with inflexible membranes that are no longer at their best. And not as many young, scar-free new cells.” - Garret Oliver, Brewmaster at Brooklyn Brewery

Here's a quick summary for those who don't have time to read it. They give scientific reasons for these conclusions, but if you want those you'll have to read the article.

Underpitch: very high attenuation (weird I know, but true), high esters, full body, great for harvesting
Standard: normal attenuation, moderate esters, full body, good for harvesting
Overpitch: very high attenuation, very clean with no esters, thin body, terrible for harvesting

Given all these results I think I would rather underpitch than overpitch for most styles and situation

 

[Chadwick]

http://sciencebrewer.com/2012/03/02/pitching-rate-experiment-part-deux-results/

Check out this, or many other links on the subject.

Here's a quote from the article (experiment was to take the same wort, a Belgian ale, and split into 3 carboys, one underpitched, one standard, and one overpitched)

"The under-pitched was fuller on the palate and contained more fruity esters that reminded me apples, pears, and some peach. The overpitch beer was clearly thinner bodied and scrubbed of many flavors. It just seemed duller. The control brew had some spicy phenolics going on and the pilsner malt really shined through."

EDIT: I actually posted that article before I read all of it. Wow! its really, really worth a read. Here's another quote that shows why overpitching can be detrimental.

"My gut feeling is that for a wort of average strength, you could cut the pitch rate from 30 – 50% and still achieve or exceed final attenuation vs a control. You’d have higher esters, but a revitalized (younger) yeast set afterwards. We will sometimes slightly underpitch when we want to put some more vigor back in a culture that otherwise seems healthy. Conversely, overpitching ages the culture – fewer daughters, over time, leaves you with a lot of battle-weary scarred cells with inflexible membranes that are no longer at their best. And not as many young, scar-free new cells.” - Garret Oliver, Brewmaster at Brooklyn Brewery

Here's a quick summary for those who don't have time to read it. They give scientific reasons for these conclusions, but if you want those you'll have to read the article.

Underpitch: very high attenuation (weird I know, but true), high esters, full body, great for harvesting
Standard: normal attenuation, moderate esters, full body, good for harvesting
Overpitch: very high attenuation, very clean with no esters, thin body, terrible for harvesting

Given all these results I think I would rather underpitch than overpitch for most styles and situation

Wow. Thanks so much for posting that. That actually explains everything. It also explains why my underpitched barleywines, like some of the ones I made years ago, was so darn good while they've been missing a certain something when I've recreated them and pitched a much larger quantity of yeast.

:rockin: You rock.

 

[divrguy]

I have been starting fermentation now at 72 and cooling down to 67 with 05. I have noticed that it takes off quite a bit faster with no ill effects on the beer. Actually tastes better imo. Whenever I started fermentation at 65-68 it seems to have chugged along and got the job done, just much slower.

I tend to pitch right at calculated pitch rates.

 

[turkeygecko]

I've had a couple weird batches with us-05 lately also, but off flavors... like, 2 out of last 4 batches, and I haven't had an infection previously, or since, with different strains. Probably just a coincidence and something dirty in my system, but us-05 was the only common denominator I found...

 

[eelpout]

I've had a couple weird batches with us-05 lately also, but off flavors... like, 2 out of last 4 batches, and I haven't had an infection previously, or since, with different strains. Probably just a coincidence and something dirty in my system, but us-05 was the only common denominator I found...

Oh yeah. Have noticed the same thing over the last year. Several members in our club are also mentioning the very long lags and off flavors.
Even double pitching don't seem to be helping the 3-4 day lags. The off flavors do clean up but in some cases it takes months. And like you said, it all leads back to the 05 batches alone.

This very stable and predictable yeast seems to have changed.
Most of us have pretty much moved away from 05 now and are comparing notes to find our next goto yeast.

 

[Chadwick]

Oh yeah. Have noticed the same thing over the last year. Several members in our club are also mentioning the very long lags and off flavors.
Even double pitching don't seem to be helping the 3-4 day lags. The off flavors do clean up but in some cases it takes months. And like you said, it all leads back to the 05 batches alone.

This very stable and predictable yeast seems to have changed.
Most of us have pretty much moved away from 05 now and are comparing notes to find our next goto yeast.

I don't really want to have to look for another go-to yeast. I like my US-05 very much. I have always had good results with it, even with the ones that have been starting slow. Apparent attenuation has been through the roof lately too. Most of my batches have been getting close to 90% apparent attenuation. I haven't noticed an increase in fusels either. This is good. I hate fusel alcohol rich producing yeasts.

I recently played around with some WLP099 and found that while the alcohol tolerance is indeed high, the fusel alcohol production was beyond what I consider acceptable. Still, i'll find a use for it. Possibly as a bottling yeast for my barleywines over 15% ABV. I haven't tried this yet, but it may be in the cards soon.

 

[foles]

I too am having this problem. No appreciable krausen, moderate bubbling that seems to have slowed down only 2.5 days after pitching commenced. Never seen this with US05. Bumped up the temp a little to try and get things moving. Will need to take a gravity reading soon.

 

[olotti]

Same here. Slow start minimal krausen but it does the job and I've hit my fg's with it but I may just use my washed wlp001 instead from now on when it calls for 05.

 

[1977Brewer]

Both of my s-05 batches in primary right now have attenuated at 85-90%, no fruity esters either. No temp control yet, but it was 60* when I pitched and warmed up a couple of days later. Now it's 30 out, so Mother Nature is cold crashing for me.

 

[ciderWI]

My last two S05 batches have started up within 12 hours and formed a thick krausen within 24 hours. Both stout, pitched the dry yeast directly in, left it in the 70 degree kitchen overnight, then down to the 65 degree basement. The first needed the blowoff tube and had FG as spec'd in the kit after a week, the second has been going for three days now and starting to slow down.

No problems, I'm impressed with it.

 

[Chadwick]

New batch, a DIPA with an OG of 1.085. This time I proofed my US-05, two packs, in an extremely mild liter starter with a gravity of only 1.010. When I pitched the starter into the wort (at 68F) the starter had a 4 inch krausen. 3 days later and my airlock is just now barely trickling with one tiny bubble slipping by every minute.

I did this same recipe a couple of years ago and within 12 hours I was in a panic to get the blow-off attached because wort was spewing out of my airlock.

You can't tell me that something hasn't changed with US-05. Still, the brews I've done with it so far these last 6 months are all attenuating well, if not better than expected. They taste good. My only complaint is the slower fermentation and an extended period needed for bottle conditioning. They are conditioning very slowly.