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I haven't done any WF lagers yet but my next brew I want to do a warm fermented bockbier with WLP833.
However, I'm guessing another advantage of WF is you don't need as much yeast to start off with so you can have a starter ready quicker with the required amount of yeast.
 
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So I got 4 kegs sitting with acetyldehyde warm lager currently crashing.
I've added gelatin to 1 keg and I've raised the temperature to 4c, perhaps a bit higher?
I will give these beers a week to see how they develop.
 
So I got 4 kegs sitting with acetyldehyde warm lager currently crashing.
I've added gelatin to 1 keg and I've raised the temperature to 4c, perhaps a bit higher?
I will give these beers a week to see how they develop.
I seriously doubt you have acetaldehyde. Acetaldehyde comes from an underpitch of very unhealthy unhappy yeast. This off-flavor is rare and over-hyped IMO. More likely with a warm lager fermentation you have an apple ester. Apple, or pear, esters, are fairly common in lagers, believe it or not, though it is usually at a very low level so as not to distract. In any case, acetaldehyde doesn’t resemble apple so much as it does raw pumpkin or latex paint. Taste again and see if you can detect one of those things instead. If not, it's probably an ester.

If you really have acetaldehyde, then be aware that this is a chemical that evaporates at 21C. So conditioning much warmer might improve it over time.

However, as I said above, I really don’t think this is your issue.

If you have an apple or pear ester, it’s permanent. No amount of conditioning will get rid of it. But you could attempt to cover it up with more hops or something like that. Or consider adding apple juice or concentrate on purpose to turn this batch into a graf (which ain't such a terrible thing).
 
I seriously doubt you have acetaldehyde. Acetaldehyde comes from an underpitch of very unhealthy unhappy yeast. This off-flavor is rare and over-hyped IMO. More likely with a warm lager fermentation you have an apple ester. Apple, or pear, esters, are fairly common in lagers, believe it or not, though it is usually at a very low level so as not to distract. In any case, acetaldehyde doesn’t resemble apple so much as it does raw pumpkin or latex paint. Taste again and see if you can detect one of those things instead. If not, it's probably an ester.

If you really have acetaldehyde, then be aware that this is a chemical that evaporates at 21C. So conditioning much warmer might improve it over time.

However, as I said above, I really don’t think this is your issue.

If you have an apple or pear ester, it’s permanent. No amount of conditioning will get rid of it. But you could attempt to cover it up with more hops or something like that. Or consider adding apple juice or concentrate on purpose to turn this batch into a graf (which ain't such a terrible thing).
Ok thanks good to know, will keep track and report back whats going on here.
Its quiet a strong ester then
 
I seriously doubt you have acetaldehyde. Acetaldehyde comes from an underpitch of very unhealthy unhappy yeast. This off-flavor is rare and over-hyped IMO. More likely with a warm lager fermentation you have an apple ester. Apple, or pear, esters, are fairly common in lagers, believe it or not, though it is usually at a very low level so as not to distract. In any case, acetaldehyde doesn’t resemble apple so much as it does raw pumpkin or latex paint. Taste again and see if you can detect one of those things instead. If not, it's probably an ester.
Okay, crap. Now I have a question. Not trying to stray off topic. I think this could help beervoid be sure of what they are dealing with here.

I'm pretty familiar with what I think is an ester profile that I can pick up to a varying degree in some lagers. I always get that as more of a prominent fruity apple/pear flavor and then rose flavor in the background. I have picked that flavor up and discussed it with others that seem to agree that it's esters. It's usually faint and not unpleasant at those low levels. Not saying I'm correct, but there you go. It's different than what I have always thought of as acetaldehyde, though.

A group I'm in just did an off flavor sensory a couple weeks ago and the acetaldehyde flavor came across to me as oxidized cider. Maybe a touch acetic. We also sampled some competition entries recently and multiple people brought up acetaldehyde for a couple different beers. Those two beers had a very similar flavor to me as the acetaldehyde off flavor sample. Not everybody tasting the entries was at the off flavor sensory but there was some cross-pollination. I also know some people described the acetaldehyde off flavor sample as pumpkin guts. I kept my mouth shut and let others talk first when tasting the competition entries. Acetaldehyde came up and was matched with the oxidized apples descriptor.

So, now I'm wondering... Could this be a difference in palates?

Acetaldehyde is not a regular flavor I come across and so I'm not as confident with it. I've never got pumpkin, but I hear that pretty often. @dmtaylor, you seem to have more experience here. I am curious what you and others have to say. @beervoid, sorry if I'm muddying the waters. Not trying to say it's acetaldehyde or lead you astray. Just trying to think it out.
 
I haven't done any WF lagers yet but my next brew I want to do a warm fermented bockbier with WLP833.
However, I'm guessing another advantage of WF is you don't need as much yeast to start off with so you can have a starter ready quicker with the required amount of yeast.
Yeah, I would say that's another advantage. I still run my WFs colder than the typical ale ferment so I pitch a little heavier than I would an ale. Still pretty short of what I'm pitching at 45-50F, though...
 
Okay, crap. Now I have a question. Not trying to stray off topic. I think this could help beervoid be sure of what they are dealing with here.

I'm pretty familiar with what I think is an ester profile that I can pick up to a varying degree in some lagers. I always get that as more of a prominent fruity apple/pear flavor and then rose flavor in the background. I have picked that flavor up and discussed it with others that seem to agree that it's esters. It's usually faint and not unpleasant at those low levels. Not saying I'm correct, but there you go. It's different than what I have always thought of as acetaldehyde, though.

A group I'm in just did an off flavor sensory a couple weeks ago and the acetaldehyde flavor came across to me as oxidized cider. Maybe a touch acetic. We also sampled some competition entries recently and multiple people brought up acetaldehyde for a couple different beers. Those two beers had a very similar flavor to me as the acetaldehyde off flavor sample. Not everybody tasting the entries was at the off flavor sensory but there was some cross-pollination. I also know some people described the acetaldehyde off flavor sample as pumpkin guts. I kept my mouth shut and let others talk first when tasting the competition entries. Acetaldehyde came up and was matched with the oxidized apples descriptor.

So, now I'm wondering... Could this be a difference in palates?

Acetaldehyde is not a regular flavor I come across and so I'm not as confident with it. I've never got pumpkin, but I hear that pretty often. @dmtaylor, you seem to have more experience here. I am curious what you and others have to say. @beervoid, sorry if I'm muddying the waters. Not trying to say it's acetaldehyde or lead you astray. Just trying to think it out.
I've never had this off flavor before in any beer.
What I can say is that I always ferment 4 kegs at the time so it would very strange if it was an infections, I had 4 kegs with the same "problem".

I would be curiois to know what it actually is.
On the nose is green apple/pear and smells sourish as well but ph is in range 4.3.
Its def not bad to drink, but its got way too much fruity things going on to be a clean beer.

What stands out to me is the low attenuation 1.012, og of the beer was 1.046, so somehow I got a sluggish ferment even though at day 3 there where almost no bubbles anymore and I let it freerise to finish off.

Having said that, I was wondering if anyone else tasted their lagers on day 10, perhaps its just the yeast in suspension? I hope so.
I will know more in a day or so when one keg which was gelatin fined will be sampled.
 
Okay, crap. Now I have a question. Not trying to stray off topic. I think this could help beervoid be sure of what they are dealing with here.

I'm pretty familiar with what I think is an ester profile that I can pick up to a varying degree in some lagers. I always get that as more of a prominent fruity apple/pear flavor and then rose flavor in the background. I have picked that flavor up and discussed it with others that seem to agree that it's esters. It's usually faint and not unpleasant at those low levels. Not saying I'm correct, but there you go. It's different than what I have always thought of as acetaldehyde, though.

A group I'm in just did an off flavor sensory a couple weeks ago and the acetaldehyde flavor came across to me as oxidized cider. Maybe a touch acetic. We also sampled some competition entries recently and multiple people brought up acetaldehyde for a couple different beers. Those two beers had a very similar flavor to me as the acetaldehyde off flavor sample. Not everybody tasting the entries was at the off flavor sensory but there was some cross-pollination. I also know some people described the acetaldehyde off flavor sample as pumpkin guts. I kept my mouth shut and let others talk first when tasting the competition entries. Acetaldehyde came up and was matched with the oxidized apples descriptor.

So, now I'm wondering... Could this be a difference in palates?

Acetaldehyde is not a regular flavor I come across and so I'm not as confident with it. I've never got pumpkin, but I hear that pretty often. @dmtaylor, you seem to have more experience here. I am curious what you and others have to say. @beervoid, sorry if I'm muddying the waters. Not trying to say it's acetaldehyde or lead you astray. Just trying to think it out.
It's been so long since I have noted acetaldehyde in any beer. It is probably easier for me to specify what it does NOT taste like, than what it does taste like. I'm pretty sure I know what esters taste like -- somewhere between red apple and pear is a common one. If I can think to myself: "does this maybe taste like pear?" and the answer is "yes" (which it always has been in the past few years), then I know it's an ester. Pear is a very common one, mostly in Belgians, but really in a lot of beers. If the answer to that same question is instead a definite "no", then the next question I would ask is: "does it taste like RED apple? or is it closer to latex paint?". That's how I split these up. It's been a long time since I tasted anything close to latex or pumpkin in any beer, but it HAS happened.

Rose character is something else entirely. Personally I might describe rose character as "perfumy" or "toilet-paper scent", which for me is a major turn-off. It's an ester, but it's not the same as apple or pear. I don't associate these together usually.

Overall, my thinking is that 9 times out of 10, when judges accuse a beer of containing acetaldehyde, they've actually probably been misled by the common "green apple" descriptor.... the beer might indeed taste like apple, but is it really "green" apple? or "red" apple? or something else entirely?? Based on good healthy pitching rates being most common these days, versus how we might have brewed ~20 years ago, what we're picking up today is actually much more likely an ester than acetaldehyde. You really have to treat your yeast in a pretty rotten fashion for it to not clean up the acetaldehyde below detectable taste threshold. I got a terrible acetaldehyde in one of my homebrews one time, this was more than 20 years ago. I was pretty sure that it was due to my major underpitch of nearly dead yeast without a starter, so it was my own fault. From then on, I pitched at a higher rate, and never experienced a similar problem again, as far as I know.

As for "oxidized cider", I think I know from experience what that tastes like... somewhere between caramel and Cheerios. Those problems are not the same as what I would expect from acetaldehyde.

And "oxidized apples"... to me that just means "rotten apples". I know what those are like as well. That ain't a good descriptor for acetaldehyde either. Rotten apples would however likely contain acetic acid, among other nasty solventy compounds including acetone. If picking up vinegar at all, consider that... it might really be vinegar, but would not necessarily have anything to do with apples or acetaldehyde.

There may be differences in palates. But more importantly, I think there are major differences in experience and education. Get 20 different judges to define acetaldehyde, and you might only get 4 or 5 different answers... but consider the possibility that maybe none of these descriptors are quite right for most of us or even all of us! Even for those who've been through an off-flavor tasting panel (I have been, about a decade ago), it's just been too long for many of us, I think, to know for sure what acetaldehyde really smells & tastes like, it's too uncommon today, or it's just not THAT off-putting of a flavor that many of us might notice?! I should get me a sample of the actual chemical again sometime to imprint it more firmly into my taste memory, because it's been probably 20 years since I've picked it up to where I would actually document it on somebody's score sheet. And I think anyone who documents this might be mistaking ester for it, I truly believe this. It was a bigger problem, but this was a long long time ago. We pitch better yeast at better rates now, generally.
 
Rose character is something else entirely. Personally I might describe rose character as "perfumy" or "toilet-paper scent", which for me is a major turn-off. It's an ester
The floral scents tend to be terpenols not esters - geraniol is the classic one - which generally come from hops and spices, but you may get yeast biotransforming one into another.

I have had a classic appley acetaldehyde from a commercial cask which had been rushed to a beer festival, but by day 3 it was fine.

A good place to find small-chain esters showing up as a sign of immaturity is in Beaujolais Nouveau when it is first released - I still remember one I had decades ago that was just pure pear drop (ie ethyl acetate, about as small an ester as you can get). Beaujolais Nouveau is an interesting example as it's rushed out in November, it's then considered to "go to sleep" for a few months and then gets much better in the spring.
 
Let me just jump in here to say “wow”.
Yeah, I suppose I asked for that...

It's been so long since I have noted acetaldehyde in any beer...

I feel like it's appropriate that I read through this whole thing once, then a second time, then found myself at the bottom of the message reading your signature that says...

"The world will become a much more pleasant place to live when each and every one of us realizes that we are all idiots."

I'd like to think I didn't just realize I'm an idiot, but it's good to be reminded from time to time...

Truly, thanks for the descriptions! I think I'm on board with those same ester flavors. Pear and red apple. I probably need to try harder to think about the kind of apple and I now also realize I haven't eaten a pear in a good while. Still thrown off by the latex paint and pumpkin description because I never got that at all with the off-flavor panel. The best I can give is that same oxidized cider, which you described both weirdly but also very accurately. I'm going to redo that panel when I get a chance and spend more time with that acetaldehyde flavor to see if I can distinguish and describe it better.

I'm going to leave the "oxidized apples" descriptor alone because that one is coming from other people, and the specific wording is also subject to my crappy memory.

Rose character is something else entirely. Personally I might describe rose character as "perfumy" or "toilet-paper scent", which for me is a major turn-off. It's an ester, but it's not the same as apple or pear. I don't associate these together usually.
The floral scents tend to be terpenols not esters - geraniol is the classic one - which generally come from hops and spices, but you may get yeast biotransforming one into another.
I definitely assume whatever I am getting here is something separate/different from the typical apple/pear. It hits separate and later and muuuuch fainter. Often I don't get it and rarely does anyone else agree. If it's not a figment of my imagination then maybe it's my shortcomings in describing it, because "perfumy" or "toilet-paper scent" make sense but are not what I would use to describe what I am getting. I'm thinking something more like the floral notes you get in some apples, like Envy or Ambrosia. More appealing than toilet paper, at least. @Northern_Brewer, thanks for the extra info. These beers aren't spiced or heavily hopped. I've gotten what I assume is strong geraniol with certain hops but I don't know if this is the same. I'll be paying more attention in the future to see if I can connect them.

There may be differences in palates. But more importantly, I think there are major differences in experience and education.
Yeah..very, very fair. All the more reason to work on my specific training/education with the one palate I've got. Again, I appreciate the input!
 
Maybe I should add,
I kettle hopped this batch for 5 gallons to approx 14IBU with
0.25 talus @45 mins
0.5 Palisade @ 15mins
0.25 talus @ 15mins

No dryhopping
 
The floral scents tend to be terpenols not esters - geraniol is the classic one - which generally come from hops and spices, but you may get yeast biotransforming one into another.

I have had a classic appley acetaldehyde from a commercial cask which had been rushed to a beer festival, but by day 3 it was fine.

A good place to find small-chain esters showing up as a sign of immaturity is in Beaujolais Nouveau when it is first released - I still remember one I had decades ago that was just pure pear drop (ie ethyl acetate, about as small an ester as you can get). Beaujolais Nouveau is an interesting example as it's rushed out in November, it's then considered to "go to sleep" for a few months and then gets much better in the spring.
The Beaujolais Nouveau example is a really good one; my brother in law would always have some for Thanksgiving and some years were straight pear juice. By Christmas time it mellowed considerably.
 
I'd like to try a warm fermented lager, yeast options right now are S23 (but sounds too ester-y from what I read), classic 34/70, MJ'S M76 (which some claim is 34/70, some swear It's not) and the new Novalager (which Is kinda expensive I must say).
Which one would you choose for a malt-forward beer?

Also, in summer here fermentation temperatures may very well get "Belgian"...
 
I'd like to try a warm fermented lager, yeast options right now are S23 (but sounds too ester-y from what I read), classic 34/70, MJ'S M76 (which some claim is 34/70, some swear It's not) and the new Novalager (which Is kinda expensive I must say).
Which one would you choose for a malt-forward beer?

Also, in summer here fermentation temperatures may very well get "Belgian"...
I you can get it, use Mangrove Jack California Lager. If not, use 3470, that is the one that always works, hard to go wrong with that one.
 
I'd like to try a warm fermented lager, yeast options right now are S23 (but sounds too ester-y from what I read), classic 34/70, MJ'S M76 (which some claim is 34/70, some swear It's not) and the new Novalager (which Is kinda expensive I must say).
Which one would you choose for a malt-forward beer?

Also, in summer here fermentation temperatures may very well get "Belgian"...

Kunze (4.4.3.1) talks about bunging pressure balancing out an increase in temperature (0.16 bar balances out a 1K increase in average temperature). I have found that this works quite well. If you ferment in a keg or other pressure capable vessel you can use any of those yeasts for a really clean lager fermented in the 60s and possibly 70s (I have not gone that high). S-23 really is a very balanced yeast under these conditions, has no fruity esters and produces fantastic light lagers.
 
I you can get it, use Mangrove Jack California Lager. If not, use 3470, that is the one that always works, hard to go wrong with that one.
I read various reports online about MJ CL and It seems not very reliable, have you used It consinstently?
 
I read various reports online about MJ CL and It seems not very reliable, have you used It consinstently?
Sometimes I did and someone's I did not.I guess the answer would be no then. I think you have to be very aware of the amount of yeast you pitch with this one. One pack might be not enough for a standard gravity standard batch size. Better use two packs.

.... Or just go with 3470.
 
You mean us05? You probably loose the lager characteristic.
Sorry, my bad, should have said Safale T-58.

I guess the question boils down to, if you mix a bottom fermenting yeast, with a top fermenting yeast with a respective ratio of 5:2 under pressure, will a conflict result with one outcompeting the other, or will they work synergistically. I posed this question to AI and it suggested that the influence of fermenting under pressure may help equalize the synergy of the two.
 
Sorry, my bad, should have said Safale T-58.

I guess the question boils down to, if you mix a bottom fermenting yeast, with a top fermenting yeast with a respective ratio of 5:2 under pressure, will a conflict result with one outcompeting the other, or will they work synergistically. I posed this question to AI and it suggested that the influence of fermenting under pressure may help equalize the synergy of the two.
I have pitched 50/50 S23 and Nottingham a number of times and nobody could tell the difference between the S23 only beer made from identical wort. While certainly not close to your example, maybe another reference point about mixing lager and ale yeast.
 
Sorry, my bad, should have said Safale T-58.

I guess the question boils down to, if you mix a bottom fermenting yeast, with a top fermenting yeast with a respective ratio of 5:2 under pressure, will a conflict result with one outcompeting the other, or will they work synergistically. I posed this question to AI and it suggested that the influence of fermenting under pressure may help equalize the synergy of the two.
Pressure inhibits yeast expression so both would be rather clean anyway. My guess is, at the given ratio, you probably couldn't tell that there's some us05 inside.

However, t58 seems to be phenolic so you could probably taste that one.
 
Quick update, as the 34/70 beer is clearing up the strong esters are subsiding, but the beer has a definite wheat beer note to it.
Even gelatin fining did take a while to get this to clear, 34/70 is not a great flocculator. Anyone know if Novalager fares better?

The previous brew I did in these kegs was a wheat beer. I clean it with oxyclean and sanitize after, I find it hard to believe there was any flavor/aroma transfer, but perhaps people here have a different view?
Next up I will try out the novalager and throw some more oldschool hops in there to see if I get better results.
 
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Quick update, as the 34/60 beer is clearing up the strong esters are subsiding, but the beer has a definite wheat beer note to it.
Even gelatin fining did take a while to get this to clear, 34/70 is not a great flocculator. Anyone know if Novalager fares better?

The previous brew I did in these kegs was a wheat beer. I clean it with oxyclean and sanitize after, I find it hard to believe there was any flavor/aroma transfer, but perhaps people here have a different view?
Next up I will try out the novalager and throw some more oldschool hops in there to see if I get better results.
3470 is clean and doesn't show any phenolic character. So if you got clove, your got an infection. Either a wild one or from the yeast of your previous beer.
 
Quick update, as the 34/70 beer is clearing up the strong esters are subsiding, but the beer has a definite wheat beer note to it.
Even gelatin fining did take a while to get this to clear, 34/70 is not a great flocculator. Anyone know if Novalager fares better?

The previous brew I did in these kegs was a wheat beer. I clean it with oxyclean and sanitize after, I find it hard to believe there was any flavor/aroma transfer, but perhaps people here have a different view?
Next up I will try out the novalager and throw some more oldschool hops in there to see if I get better results.
Novalager is a great WF lager yeast; their major selling point is absolutely NO sulfur production, and low esters on either end of the temperature range. However, the flocculation isn't terrific. Lallemand lists the flocculation as moderate. I've kegged two batches using it so far; the first had gelatin added at kegging, the second did not (because I forgot). The first one didn't become what I would call clear for at least 12 days in the keg. The second one was kegged on 4/1, has been lagering ever since, and is still hazy. Unless a beer is going to competition, I don't really care if I can read a phone book through it, but I do like to see a bright clear pretty beer in my glass.
 
Novalager is a great WF lager yeast; their major selling point is absolutely NO sulfur production, and low esters on either end of the temperature range. However, the flocculation isn't terrific. Lallemand lists the flocculation as moderate. I've kegged two batches using it so far; the first had gelatin added at kegging, the second did not (because I forgot). The first one didn't become what I would call clear for at least 12 days in the keg. The second one was kegged on 4/1, has been lagering ever since, and is still hazy. Unless a beer is going to competition, I don't really care if I can read a phone book through it, but I do like to see a bright clear pretty beer in my glass.
I found that the moment it cleared up it also tasted much better, the yeast in suspension doesnt do the beer a favor imho.
 
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