Help identifying off-flavor/ potential characteristic of the yeast?

the_goat_Birdman

Member
Trial Member
Established Member
Joined
Mar 21, 2024
Messages
56
Reaction score
45
Points
18
Hello All,

I have been having bad luck with Belgian yeast recently. My first batch was a Belgian Wit, with coriander and orange peels. Although I know where I messed up on that one (pitching when wort was too warm), this recent brew has the same issue. It is an 805 Clone, the link to the recipe is here: https://byo.com/wp-content/uploads/woocommerce_uploads/Firestone-Walker-clones-3.pdf

I used Fermoale Ay-3, which on the label says is perfect for English ales and Belgians. I pitched at 65 degrees wort internal temp, allowed it to warm up naturally to 68, and held it there for a week. It hit FG today of 1.012, starting at 1.055. The aroma is a strong cider, with a hint of sulfur. I expected the sulfur, but not the cider. The cider smell is very strong, but doesn't carry into the beer itself. In my previous brew, I had a strong cider smell as well, and was also using a yeast meant for belgians. Is this cider smell typical for Belgian yeasts? or is this the presence of an infection? I sanitize using star san diluted to the requirements and test with a PH meter.
 
Acetaldehyde is usually associated with apple. At 68F, Acetaldehyde shouldn't be an issue.

are you pressure fermenting by any chance?
 
As noted, apple, especially green apple, is acetaldehyde. That comes from not letting it ferment long enough.

Once the gravity has stopped, you should try to leave it on the yeast for at least another three days, or longer. Even though the alcohol production is done, yeast still needs time to clean up all of its byproducts, including acetaldehyde.

Not saying that's the problem, because I'm not there to smell it, but it is not uncommon.

As for the Sulphur, that will dissipate over time. It might take a few weeks or longer depending on how strong it is. But eventually it will be perfectly drinkable
 
I haven't done a Wit. I have done some Belgian beers and a couple of Saisons. Make sure you are following the instructions on the yeast packet. Do some online and Youtube searches about where that specific yeast is happy. With the Belgian monastery yeasts and Saison yeasts, they like to start about 68, and get ramped up over a few days. The one other thing they are notorious for is needing some patience. That beer might be fermented in 14 days (and, yes, keep it in the fermenter for 14 days. Do not rush it), but you need to give them a little extra time before making a decision about not liking the beer. I had a Saison that I hated after I bottled it. I gave it another two weeks, and it was good. Another two weeks, it was awesome.
The Dubbel that I made last winter was wonderful after being in the keg for about 3 weeks. Just saying.
You can't rush good beer, especially Belgians.
 
Acetaldehyde is usually associated with apple. At 68F, Acetaldehyde shouldn't be an issue.

are you pressure fermenting by any chance?
No, no pressure fermenting. It is in a stainless steel bucket fermenter. I have had the beer cold crashing for about 12 hours. Should I still warm it up and allow it to clean up like these others are suggesting?
 
As noted, apple, especially green apple, is acetaldehyde. That comes from not letting it ferment long enough.

Once the gravity has stopped, you should try to leave it on the yeast for at least another three days, or longer. Even though the alcohol production is done, yeast still needs time to clean up all of its byproducts, including acetaldehyde.

Not saying that's the problem, because I'm not there to smell it, but it is not uncommon.

As for the Sulphur, that will dissipate over time. It might take a few weeks or longer depending on how strong it is. But eventually it will be perfectly drinkable
I had some family try the beer. They noted a vegetable like flavor. I think this is DMS from not boiling long enough. If I allow the beer to come back up to temp in the fermenter (I started cold crashing before this post) will it still clean up the DMS and possible acetaldehyde?
 
No, no pressure fermenting. It is in a stainless steel bucket fermenter. I have had the beer cold crashing for about 12 hours. Should I still warm it up and allow it to clean up like these others are suggesting?
you could try it. it certainly wont hurt, but the yeast may have dropped out enough by now.

I had some family try the beer. They noted a vegetable like flavor. I think this is DMS from not boiling long enough. If I allow the beer to come back up to temp in the fermenter (I started cold crashing before this post) will it still clean up the DMS and possible acetaldehyde?
yeast wont really clean up DMS, drive that off durring the boil is really the best way to avoid it. from what you describe, I doubt that is it anyway. DMS tastes like creamed corn. you were describing more of a hydrogen sulfide smell
 
Short answers: try warming it, no harm, could help.

And venting the steam during boil is the only way to rid the dms. That, unfortunately, won't go away now. Don't ask how I learned that...

But, in the bigger picture, some valuable experience has been gained. Brew on!
 
Thanks all! I will let it come up to room temperature which is about 77 degrees here. Is that too warm considering I fermented at 68?
 
Cider off smell /flavour is definitely not typical for Belgium beers.
I have no experience with the yeast you are using, google says 16-23 oC (61-73 F), so a cooler spot would be better
 
Thanks all! I will let it come up to room temperature which is about 77 degrees here. Is that too warm considering I fermented at 68?
It won't hurt it. A warmer rest has the best chance of processing the acetaldehyde. If the other off flavour is dms, I think you are stuck with it, if it is hydrogen sulfide, good chance it will go away
 
I question the health and pitch rate of your yeast for the acetaldehyde.
According to the specs on the yeast below, you were in the correct temp range. Also a low H2S producer.
Cider? That's either to much simple sugar( not in the recipe) or infection.
Was this an extract brew? LME or DME? If so, how old was the extract? LME after 6 months tastes like crap. DME is better for much longer.
DMS? This doesn't age out and is caused from not enough evaporation during the boil and post boil until you get below 150° on the cool down.

I'd start with a soak and deep clean of everything. Use PBW and hot water. Wash cloth only, nothing abrasive. A good rinse, and put away dry. Then sanitize anything that is used post boil in your next session.
Eliminate any LME and replace with DME in your recipe.
Boil uncovered for at least 60 minutes and keep uncovered while cooling until you drop to 150°.
Finish cooling to ~65° and then pitch a healthy yeast. I'd suggest you use dry yeast getting started and pitch the correct amount or a bit more.
https://www.lallemandbrewing.com/en...brewing-calculators/pitching-rate-calculator/
No need to aerate with the dry yeast, just sprinkle on top of the cooled wort.
Hopefully this will correct your issues.
Good Luck,
Brian


BREWING PROPERTIES
YEAST STRAIN: Saccharomyces cerevisiae
ORIGIN OF YEAST STRAIN: UK
APPARENT ATTENUATION: 75-83% | High
FERMENTATION TEMPERATURE: 16-23°C | 61-73°F
FLOCCULATION: High
ALCOHOL TOLERANCE: 12% ABV
TOTAL ESTERS: Low
H2S (SULPHUR NOTES): Low
POF (PHENOLIC NOTES): Negative
STA-1: Negative
 
I question the health and pitch rate of your yeast for the acetaldehyde.
According to the specs on the yeast below, you were in the correct temp range. Also a low H2S producer.
Cider? That's either to much simple sugar( not in the recipe) or infection.
Was this an extract brew? LME or DME? If so, how old was the extract? LME after 6 months tastes like crap. DME is better for much longer.
DMS? This doesn't age out and is caused from not enough evaporation during the boil and post boil until you get below 150° on the cool down.

I'd start with a soak and deep clean of everything. Use PBW and hot water. Wash cloth only, nothing abrasive. A good rinse, and put away dry. Then sanitize anything that is used post boil in your next session.
Eliminate any LME and replace with DME in your recipe.
Boil uncovered for at least 60 minutes and keep uncovered while cooling until you drop to 150°.
Finish cooling to ~65° and then pitch a healthy yeast. I'd suggest you use dry yeast getting started and pitch the correct amount or a bit more.
https://www.lallemandbrewing.com/en...brewing-calculators/pitching-rate-calculator/
No need to aerate with the dry yeast, just sprinkle on top of the cooled wort.
Hopefully this will correct your issues.
Good Luck,
Brian


BREWING PROPERTIES
YEAST STRAIN: Saccharomyces cerevisiae
ORIGIN OF YEAST STRAIN: UK
APPARENT ATTENUATION: 75-83% | High
FERMENTATION TEMPERATURE: 16-23°C | 61-73°F
FLOCCULATION: High
ALCOHOL TOLERANCE: 12% ABV
TOTAL ESTERS: Low
H2S (SULPHUR NOTES): Low
POF (PHENOLIC NOTES): Negative
STA-1: Negative
Thanks Brian. I did an all-grain recipe, with no LME or DME additives. There were also no sugar additions. I typically clean my vessel with PBW heated to 120 degrees and a sponge. The Fermoale pack was the dried version (I think all varieties offered by them are dry). I pitched 1 package into a 65 degree wort with an OG of 1.055.
 
To everyone on this thread, I took the fermenter out of the fridge and set it in a cold spot in my room. This morning, the beer has started bubbling again. Very very slowly, but there are bubbles. I am thinking I began cold crashing too early, and the yeast simply did not have enough time to clean everything up. I am going to leave it for a week or so at room temp and see what happens. Cheers all!
 
Fingers crossed ;)
 
You can also run your pbw wash at 160F. It becomes antibacterial at this temp and helps the chemical work better.

If it got going again that quickly, it needed more time
 
To everyone on this thread, I took the fermenter out of the fridge and set it in a cold spot in my room. This morning, the beer has started bubbling again. Very very slowly, but there are bubbles. I am thinking I began cold crashing too early, and the yeast simply did not have enough time to clean everything up. I am going to leave it for a week or so at room temp and see what happens. Cheers all!
give it a good swirl after it warms up without opening it up
 
It has been swirled! Bubbles are about 1 every 2 minutes. Hopefully it will clear up.
 
Bubbles have picked up quite a bit. I definitely began cold-crashing too soon. Now at about 3-4 bubbles a minute. Strange that the beer stopped bubbling completely at 68 F but has picked up a lot at 75
 

Back
Top