Stuck fermentation with every batch so far

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LanigansBall

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I'm driving myself insane trying to figure this out alone, so I figured it was time to try out the forums. The basic situation is every ale of every style I've made with safale US-05 and S-04 have stalled fermentation somewhere around the 1.025 gravity range. One of the only times I've cracked 4% was when my OG was so high that 1.025 was actually a decent drop.

For general context, I routinely mash between 155 and 165 Fahrenheit (though closest to 160). I generally do long boils because fly sparging pushes my pre-boil volumes pretty high and I add my hop pellets directly to the wort. I cool the wort to between 65 and 70 with an ice bath and aerate with a sanitized whisk and a plastic insert in the tubing I attach to my kettle's valve spout. Finally, I ferment in my basement where the temperature never goes below 60 or above 70 (US-05 and S-04's supposed sweet spot) with the beer in plastic buckets with grometted lids for the airlocks. I've kept myself to Safale US-05 and S-04 because I'm just starting out and don't want to mess around with crazy yeasts yet, plus the low cost is attractive. I keep my dry yeast packets in the fridge, which isn't supposed to hurt them, then take them out and bring them up to room temperature on brew days. I get about a 24 hour lag time, then pretty vigorous fermentation for three or four days. I've left the beer to ferment for anywhere between one week and a full month, even though Safale says these strains should only take a week at most.

I clean and sanitize just like I should and nothing's tasted bad, wrong, or infected, so I've ruled out outside contamination. I even got the compliment from a much more experienced homebrewer that my tastes were on the mark, I just needed to improve my attenuation.

To combat it, I've tried pitching two packets, changing my mash temperature, increasing my aeration, making yeast starters, cooling my wort to exactly fermentation temperature during the ice bath, and repitching packets a few days after vigorous fermentation stops. I even bought an electric thermometer, just in case my kettle's built-in dial was reading wrong. It was, but not so drastically that I was accidentally denaturing enzymes or anything. The only thing I haven't tried is artificially increasing my fermentation temperature, which other threads have recommended, mainly because with the cold weather the main part of my house is actually colder than the basement and I don't currently have the means to wrap my fermenters with any of those special warmers or anything.

I can't believe I'm the only person to have experienced this, being that these yeast strains are so common and get such high and consistent reviews, which means I must be doing something wrong. But if I am, I just can't see it.
 
Yeah it's almost certainly down to the mash temp. Do you have anything in a fermenter right now? If so, you could try adding amylase enzyme and see if that does anything. It will break down the long-chain sugars you are probably creating with your mash temp. Otherwise, mash at 150 in your next batch and see what happens.
 
Does the beer your make taste good? Give you a buzz? If so, then my first thought is that maybe there is a problem with the way you are measuring OG.
 
I agree with the others, 160-165F is awfully high. Still, punking out at 1.025 seems on the high side based on your report that 160F is your most frequent temp. Although, I'm assuming you're using a standard grist that isn't loaded down with excessive amounts of crystal and/or unmalted grains.

You might also want to look at your thermometer. You might think you're mashing at 160F when you're actually substantially higher than that. It's not enough to trust it, you have to prove that it's trustworthy by calibrating it and establishing that it holds calibration. I wasted a lot of time when I first started because I ran through a series of thermometers that were basically junk. Eventually, I stumbled on the Thermapen and life has been good ever since.

Last, are you doing an iodine test? It's a cheap and simple way to confirm that your mash is behaving as it should.
 
10 posts and nobody has asked if OP is checking FG with a hydrometer or a refractometer - without correction. C'mon, HBT... :)

155-160 are perfectly fine mash temps. Over 160, attenuation starts to plummet. Also, we don't have any OG values to judge attenuation against.

So, how are we checking gravity?
 
10 posts and nobody has asked if OP is checking FG with a hydrometer or a refractometer - without correction. C'mon, HBT... :)

155-160 are perfectly fine mash temps. Over 160, attenuation starts to plummet.

So, how are we checking gravity?
sure we did?
 
Thanks for so many good replies so quickly.

For the mash temp, that's a relatively recent change. Before, I was mashing around 150, though this could also be in doubt because it was before I had my digital thermometer. It was also a change that was recommended by a homebrewing friend who gets consistently good results. I may have misunderstood him though. Maybe he was just giving me steeping advice, even though we wouldn't have been talking about that. And I knew about the long sugars, but I wasn't opposed to it because I tend to like that sweeter, heavy characteristic. I don't know all the chemistry of it, but to me those long sugars don't account for a full .020's worth of gravity difference. In any case, the consensus seems to be that it's too high, so I'll drop it back down in the future.

The errors in OG and FG occurred to me, so I put the hydrometer in some normal tap water. It read a flat 1, so I think I'm good on that front. Unless there's some kind of error I could be making in the math for FG? It's the bottom of the meniscus on the hydrometer, right? Then ABV is calculated by using the difference between the two measurements?

I'm definitely going to try that amylase. I have three fermenting right now and if that could save them, I'm more than willing to try.
 
10 posts and nobody has asked if OP is checking FG with a hydrometer or a refractometer - without correction. C'mon, HBT... :)

155-160 are perfectly fine mash temps. Over 160, attenuation starts to plummet. Also, we don't have any OG values to judge attenuation against.

So, how are we checking gravity?

I mentioned my hydrometer in the original post, but you mentioned a correction. I don't know anything about FG corrections beyond temperature.
 
I mentioned my hydrometer in the original post, but you mentioned a correction


i didn't see hydrometer mentioned specificaly. but being you mentioned meniscus in your other post, sorry. just gotta be sure! :mug:

(this is a floaty thing right? not something you shine light through? just to be absolutly sure, i've never used a refractometer. not sure if they have a dip in the reading, ;))
 
I did a text search on the page and didn't see any reference to either hydrometer or refractometer in your original post. Okay, if you measured 1.025 with a hydrometer, then so be it.

Mashing at 156-158 is not problematic. You should get 70-75% attenuation with many yeasts at that range. You should reveal a bit more:

Yeast types
OG and FG examples (one without the other is not helpful to diagnosis)
 
I had this exact problem for a while before I figured out what was happening. I figured it out when I got a tilt hydrometer and was able to track attenuation and temperature constantly.

At the time, I was fermenting in the basement that stays a pretty constant 60F. Looking at graph after graph, I could see the temperature of the beer free-rise as gravity dropped. There always came a point where temp started to dive (1.030ish on most beers), and attenuation rapidly stopped high at that point on every batch.

I decided to get a ferm-wrap and did another batch, letting the temp free-rise and constantly setting the controller to the temp the beer was at every day. This caused the ferm-wrap to catch the temp dive when it happened and lo and behold, temp line went flat but attenuation continued right down to 1.011.

To this day I get full attenuation every time by preventing that temp dive, and even ramping temp up a few degrees at the end.

Your results may differ, but that's what worked for me when I was getting stuck in the 20's
 
I'm also looking to your mash temp as the problem here. Also wondering how long you are mashing? Try 148F @ 90 min, you should be able to dry those babies out good by doing that. What are your recipes looking like, are they heavy in special grains? Temp fluctuations aren't good for yeast, but I doubt that's causing severe attenuation problems in your case.
 
Agree mash temperatures are too high. I once had a standard thermometer which needed calibration, it was reading about 8 degrees F off. It was causing fermenting issues like yours. Also agree add amylase enzyme to fermenter to help this batch break it up more.
 
I can't believe I'm the only person to have experienced this, being that these yeast strains are so common and get such high and consistent reviews, which means I must be doing something wrong. But if I am, I just can't see it.
What you are doing different from most people is mashing at a higher temperature and fermenting without fermentation temperature control. It's possible that both of these (higher mash temp, lack of temperature control) are a factor here.

The basic situation is every ale of every style I've made with safale US-05 and S-04 have stalled fermentation somewhere around the 1.025 gravity range.
For you next batch, you could perform a Fast Ferment Test (e.g. https://www.braukaiser.com/wiki/index.php/Fast_Ferment_Test) while the rest of the batch is fermenting.

I ferment in my basement where the temperature never goes below 60 or above 70 (US-05 and S-04's supposed sweet spot)
Is 60 to 70 the ambient temperature range during the fermentation? People who are successful at fermenting at ambient temperatures tend to report a tight ambient temperature range (e.g. 62-63). A thermometer that measures daily high / low room temperature is really helpful for knowing that the room temperature is stable-enough.

See also what @brewdude88 said back in #17.
 
i didn't see hydrometer mentioned specificaly. but being you mentioned meniscus in your other post, sorry. just gotta be sure! :mug:

(this is a floaty thing right? not something you shine light through? just to be absolutly sure, i've never used a refractometer. not sure if they have a dip in the reading, ;))
Sorry, you're right. I didn't specifically mention my hydrometer. To be honest, I always forget refractometers exist.
 
I did a text search on the page and didn't see any reference to either hydrometer or refractometer in your original post. Okay, if you measured 1.025 with a hydrometer, then so be it.

Mashing at 156-158 is not problematic. You should get 70-75% attenuation with many yeasts at that range. You should reveal a bit more:

Yeast types
OG and FG examples (one without the other is not helpful to diagnosis)
Yeast is Safale US-05 and S-04, with most recent batches being US-05.

My OG's have been anywhere from 1.040 to 1.070, so I wasn't sure how helpful that was going to be to mention. Most have been somewhere around 1.055.
 
I had this exact problem for a while before I figured out what was happening. I figured it out when I got a tilt hydrometer and was able to track attenuation and temperature constantly.

At the time, I was fermenting in the basement that stays a pretty constant 60F. Looking at graph after graph, I could see the temperature of the beer free-rise as gravity dropped. There always came a point where temp started to dive (1.030ish on most beers), and attenuation rapidly stopped high at that point on every batch.

I decided to get a ferm-wrap and did another batch, letting the temp free-rise and constantly setting the controller to the temp the beer was at every day. This caused the ferm-wrap to catch the temp dive when it happened and lo and behold, temp line went flat but attenuation continued right down to 1.011.

To this day I get full attenuation every time by preventing that temp dive, and even ramping temp up a few degrees at the end.

Your results may differ, but that's what worked for me when I was getting stuck in the 20's
Is 60 to 70 the ambient temperature range during the fermentation? People who are successful at fermenting at ambient temperatures tend to report a tight ambient temperature range (e.g. 62-63). A thermometer that measures daily high / low room temperature is really helpful for knowing that the room temperature is stable-enough.

See also what @brewdude88 said back in #17.
My temperature range fluctuates with the seasons, so it's consistent over the course of the average fermentation.

I'm interested in the temp dive @brewdude88 mentioned. Any idea on what causes that? Is it mainly the exothermic fermentation slowing down?
 
i don't want to sound like the guy asking "is it plugged in". but there is space under the hydro? it's not sitting on the bottom of the test jar or something is it? ;) :mug: 😛
 
i don't want to sound like the guy asking "is it plugged in". but there is space under the hydro? it's not sitting on the bottom of the test jar or something is it? ;) :mug: 😛
I've worked in IT, so I get where you're coming from. No, always plenty of space below for an accurate reading.
 
I've worked in IT, so I get where you're coming from. No, always plenty of space below for an accurate reading.


LOL, sorry for that. had to check. what does it read in plain water again? another appolagy if that's been mentioned? and can you post a pic of said hydro?

it's odd you'd get the same FG of 1.025, with a OG range as spread out as 1.040-1.070
 
I've had attenuation issues with Omega's Voss Kveik. Personally, I think you're mashing too high and would recommend something as the others have said in the 148-152 range. You also could experiment with a step mash: 30 min. at 143, 30 min. at 152, 30 min. a 158 or something along those lines. That should surely eliminate any conversion issues from your mash and at least eliminate that as a variable for your high FGs.

However, assuming your mash temperature is converting where you're at, then I would look at fermentation temperature and yeast nutrient as possible culprits. Again, though, I'd try a lower mash temperature before I did anything else.

Edit: Sorry, the point for mentioning the Voss was that I determined that low fermentation temperatures and yeast nutrients were the likely culprits in its underattenuation.
 
Is it mainly the exothermic fermentation slowing down?

Exactly, the steep drop in temperature as fermentation was slowing seems to have been causing my yeast to go dormant a little early.

My fermentations outside of my temp controlled chamber tend to start at 60ish, then free-rise to 68ish during vigorous fermentation. It is when the yeast activity stops creating enough warmth on its own that the old inkbird kicks in and keeps the temp from diving back down.

Maybe there's another variable, but I have been getting attenuation consistently in the 80% range since I started controlling that drop in temp.
 
Exactly, the steep drop in temperature as fermentation was slowing seems to have been causing my yeast to go dormant a little early.

My fermentations outside of my temp controlled chamber tend to start at 60ish, then free-rise to 68ish during vigorous fermentation. It is when the yeast activity stops creating enough warmth on its own that the old inkbird kicks in and keeps the temp from diving back down.

Maybe there's another variable, but I have been getting attenuation consistently in the 80% range since I started controlling that drop in temp.
My only question then is why would it matter if the ambient room temperature is well-within the yeast's preferred range?
 
My only question then is why would it matter if the ambient room temperature is well-within the yeast's preferred range?

My experience has me convinced it's not a matter of the temperature being in the range for the yeast, but a sudden drop from the high temperature achieved during fermentation that signals the yeast to begin the process of going dormant.

It's kind of like seeing folks from Arizona come to Colorado and hurriedly put a coat on as they walk out of the airport on a beautiful 70F day.
 
30 posts and I still don't know what you're brewing. US-05 makes me think IPA or something pale, so I assume you aren't brewing with Lactose or anything else unfermentable that would jack up your FG.
 
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30 posts and I still don't know what you're brewing. US-05 makes me think IPA or something pale, so I assume you aren't brewing with Lactose or anything else unfermentable that would jack up your FG.
I've been doing ales across the board, so I wasn't sure if that would actually be helpful. So far I've done Irish reds, stouts, cream ales, IPAs, and brown ales, to name a few. Nothing with lactose or anything that would give me those kinds of readings, no.
 
My experience has me convinced it's not a matter of the temperature being in the range for the yeast, but a sudden drop from the high temperature achieved during fermentation that signals the yeast to begin the process of going dormant.

It's kind of like seeing folks from Arizona come to Colorado and hurriedly put a coat on as they walk out of the airport on a beautiful 70F day.
That's a good analogy. Are there ways to prevent it short of buying fermenter wraps? I'm not really in a position to buy more equipment right now.
 
I've been doing ales across the board, so I wasn't sure if that would actually be helpful. So far I've done Irish reds, stouts, cream ales, IPAs, and brown ales, to name a few. Nothing with lactose or anything that would give me those kinds of readings, no.
And every single one of them stalls at 1.025? That‘s gotta be a measurement error. Have you tried a different hydrometer?
 
And every single one of them stalls at 1.025? That‘s gotta be a measurement error. Have you tried a different hydrometer?
They don't all stall exactly at 1.025, just around it. Some stay up at 1.027, other get down to 1.020. It likely isn't a measurement error because checking the gravity of tap water gives me exactly 1.000. I haven't checked with another because this one's been accurate for the OGs (and tap water), as far as I can tell.
 
They don't all stall exactly at 1.025, just around it. Some stay up at 1.027, other get down to 1.020. It likely isn't a measurement error because checking the gravity of tap water gives me exactly 1.000. I haven't checked with another because this one's been accurate for the OGs (and tap water), as far as I can tell.
That's weird, man. You sound like a guy that knows his process. Wonder if we're just getting weaker yeast these days or something.
 
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