So I recently brewed an ESB and pitched with Wyeast 1968 ESB yeast, I know that its a bit of a difficult yeast (and beer) to get just right but I way overshot my OG and that gave me a way undersized yeast starter. I'm not a yeast expert so I'm just wondering what effects under pitching will have, I think I might be under by as much as 62 billion cells (using Beersmith calc). I did get good fermentation, went from 1.07 to 1.02 but the beer tastes like ****, basically just good for getting drunk and probably hungover. I did a diacetyl rest and had fermentation temps in the proper range also.
Underpitched = off flavours?
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I've never used that particular yeast, but with underpitching you can get more esters being produced. Banana, stone fruit, horse rectum, etc. Those usually aren't desirable. It may also be why you finished at 1.020, but obviously I don't know your recipe.
casesensative
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Underpitching is a definite cause of many different off flavors as you are stressing the yeast when you do that. Consistent fermentation temp is another very important thing.
1968 is a great yeast but finicky.
It likes to be pitched slightly cold and allowed to rise, I like to ferment it at 62-64, but as it slows it needs to be roused and warmed a few more degrees to finish.
It is highly flocculant so without the warm up it tends to drop earlier. The beer clears extremely well and leaves a very slight fruity element compared to a clean ale yeast.
Btw, 1.070 is kind of high for an ESB, was this an all grain batch?
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It likes to be pitched slightly cold and allowed to rise, I like to ferment it at 62-64, but as it slows it needs to be roused and warmed a few more degrees to finish.
It is highly flocculant so without the warm up it tends to drop earlier. The beer clears extremely well and leaves a very slight fruity element compared to a clean ale yeast.
Btw, 1.070 is kind of high for an ESB, was this an all grain batch?
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How do you package the beers you use this yeast in?
kal
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What temp did you ferment at?
WY1968 as other have said is finnicky and can drop out if you have temp swings. Try and keep ferm temp stable and below 70F. I would often give it a gentle stir myself near the end as it tends to floc out.
It also doesn't attenuate very low so when I use it I mash low (ex: 148F when making a Fullers ESB clone). Because of the low attenuation you have to be careful with your grain bill - not to introduce too many sugars that can't ferment with (for example) crystal malts.
What was your recipe? Looking at my notes I tend to get about 73-75% attenuation with WY1968 with the few recipes I've done. If you start at 1.070 and finished at 1.020. that's 71.4% attenuation which is in the range that Wyeast actually states: 67-71%
Kal
Kal
WY1968 as other have said is finnicky and can drop out if you have temp swings. Try and keep ferm temp stable and below 70F. I would often give it a gentle stir myself near the end as it tends to floc out.
It also doesn't attenuate very low so when I use it I mash low (ex: 148F when making a Fullers ESB clone). Because of the low attenuation you have to be careful with your grain bill - not to introduce too many sugars that can't ferment with (for example) crystal malts.
What was your recipe? Looking at my notes I tend to get about 73-75% attenuation with WY1968 with the few recipes I've done. If you start at 1.070 and finished at 1.020. that's 71.4% attenuation which is in the range that Wyeast actually states: 67-71%
Kal
Kal
MindenMan
Well-Known Member
WY1968 is the only yeast I use, and since I have kept a tight control on the fermentation temperature, I get predictable results. I start all of my beers at 62* F, and usually will hold 62* F for two weeks, then take a gravity sample to see where it is just for comparison, and slowly raise the temperature up to 70* F over the course of two or so weeks. Since I ferment "cold", I don't worry about needing a D-rest. This the same procedure I always use, and recently won a Best of Category Stouts and Porters. It ain't broke, and I ain't gonna "fix" it either,.
kal
Well-Known Member
MindenMan: Yours is not that different from my fermentation schedule with WY1968 - I start just a tad higher (64-66F) and then rise slowly to 68-70F and hold for a week or so once I'm a few points from terminal gravity. Like you said, if it ain't broke, don't fix it!
Kal
Kal
403Brewer
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I followed a lot of the direction from the ESB thread (like 80+ pages...which I hadn't read before I bought my ingredients) regarding the pitching temps, the 64-68-64 method was what I used. I was shooting for 1.059 I think but my efficiency was 10% higher than anticipated haha, either that or the store gave me the wrong weights. The flavour I'm getting is diacytal I think, its drinkable, not acidic or anything just not great, also is not very clear, and its in bottles which also seems to be discouraged with this yeast
insanim8er
Well-Known Member
Low pitching can lead to excessive diacetyl production. Does it taste like butter?
I see you did a d rest. Most of the time the yeast will clean up the diacetyl if allowed to. Sometimes the diacetyl is too much for the yeast to fully consume.
I see you did a d rest. Most of the time the yeast will clean up the diacetyl if allowed to. Sometimes the diacetyl is too much for the yeast to fully consume.
403Brewer
Well-Known Member
I think raising to 68 was supposed to be the rest according to the ESB brewing schedule, but I probably didn't leave it there long enough, only a few days...then dropped the temp again, certainly a learning experience brew haha...think I'll stick to the ales for a bit as that was only my 4th AG brew
insanim8er
Well-Known Member
Ya. Normally it's 24/48 hours.
The issue is you could've caused too much by under pitching.
Is the off flavor buttery? Like the buttered flavor on popcorn.
The issue is you could've caused too much by under pitching.
Is the off flavor buttery? Like the buttered flavor on popcorn.
403Brewer
Well-Known Member
Ya I'm quite sure what's what I'm tasting...I need to familiarize myself with the diacetyl flavor better, the fake butter from popcorn is great way to do that, good call!
Do you typically do a diacetyl rest for all types of yeast or do only some require it? I'm fermenting a Casacde ale with Wyeast 1056 at the moment @ 66 F, and should not be under pitched this time as my OG was correct and had an ample starter.
Do you typically do a diacetyl rest for all types of yeast or do only some require it? I'm fermenting a Casacde ale with Wyeast 1056 at the moment @ 66 F, and should not be under pitched this time as my OG was correct and had an ample starter.
insanim8er
Well-Known Member
Imitation butter flavors are in fact diacetyl, so it is a good way to learn the flavor. Some yeasts are more susceptible to diacetyl productionfor example Ringwood 1187. Other clean fermenting yeasts are less susceptible.
My general fermentation schedule allows the yeast to clean up after its self, so ya I pretty much always do a d rest for those styles that don't benefit from some diacetyl.
kal
Well-Known Member
+1
I'm never in a hurry to get the beer off the yeast, even with beers that don't need a D-rest. Leaving the beer on the yeast for a full week after you hit the FG will either do nothing at all, or only make the beer better.
If you're running a commercial brewery you need to keep things moving (fermenters are what's always in short supply) so they keep a close eye on flavour, diacetyl, etc. For home use we're lucky - we can just let it sit longer.
Kal
SpeedYellow
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Sounds unlikely that pitching rate was your problem. How many cells do you estimate you pitched, and how much is recommended for this beer?
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403Brewer
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Well using beer smith...I needed 225 billion based on the planned OG, so I made a starter for that but with an OG of 1.070 after overshooting it I needed 270 billion, so I'd be under by ~20%, assuming my original starter was perfect.
SpeedYellow
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Then it DEFINITELY wasn't a starter size problem. Pitching just 20% shy of the "recommended" amount is close enough, heck so is 50%. There's very little understanding of the impact of pitching rate on flavor, but especially in cases like yours, it's a secondary issue. Folks get too wrapped up over the current hot issues like pitching rate and mash pH when there are more important factors (recipe design and fermentation temperature schedule being the biggies).
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403Brewer
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Ya thats kind of why I wanted to get to the bottom of this, the recipe design and temp schedule seem to be pretty consistent with what the guys on the huge ESB/1968 yeast thread go with, same with the the ferm temps. The major thing I think was the bottle conditioning which apparently with the 1968 yeast does not respond well.
insanim8er
Well-Known Member
Just because someone says something with such conviction, doesn't always make it true.
I'm not saying he's wrong, because he may not be. But there's more to it.
Underpitching does not always cause undesirable off flavors, so your beer may come out great 99% of the time; however, saying that it's ok to under pitch by 50% simply isn't true. Underpitching is done deliberately in an effort to produce off flavors that are desirable in particular beers. Not all beers benefit from such flavors. I under pitched my saison on friday. People will often under pitch for hefs too. They want to bring out the esters, banana, clove.. etc.
Diacetly can be produced for several reasons-underpitching, long lag times, stressed yeast... It can even happen due to infection.
We don't know if you're even tasting diacetyl. We're just assuming. It could be something else you're actually tasting, but to assume that diacetyl was produced due to a lack of sufficient viable yeast is not far fetched especially when working with a yeast that is known for diacetyl production.
He is correct in stating that it could be something else. Often times it requires a "perfect storm" for something to occur-meaning it's not simply one thing that caused an issue. Because of that, it can be difficult to pinpoint the exact problem. It can be especially difficult when trying to get someone to explain their exact process to pin point an issue.
You could've under pitched, you could've under oxygenated; your temp controlled environment could've been off in temp; you could've made your yeast starter months ago then refrigerated it which would lower the viability of your yeast; you could've made yeast starters for way too many generations basically mutating your yeast.
I'm not saying he's wrong, because he may not be. But there's more to it.
Underpitching does not always cause undesirable off flavors, so your beer may come out great 99% of the time; however, saying that it's ok to under pitch by 50% simply isn't true. Underpitching is done deliberately in an effort to produce off flavors that are desirable in particular beers. Not all beers benefit from such flavors. I under pitched my saison on friday. People will often under pitch for hefs too. They want to bring out the esters, banana, clove.. etc.
Diacetly can be produced for several reasons-underpitching, long lag times, stressed yeast... It can even happen due to infection.
We don't know if you're even tasting diacetyl. We're just assuming. It could be something else you're actually tasting, but to assume that diacetyl was produced due to a lack of sufficient viable yeast is not far fetched especially when working with a yeast that is known for diacetyl production.
He is correct in stating that it could be something else. Often times it requires a "perfect storm" for something to occur-meaning it's not simply one thing that caused an issue. Because of that, it can be difficult to pinpoint the exact problem. It can be especially difficult when trying to get someone to explain their exact process to pin point an issue.
You could've under pitched, you could've under oxygenated; your temp controlled environment could've been off in temp; you could've made your yeast starter months ago then refrigerated it which would lower the viability of your yeast; you could've made yeast starters for way too many generations basically mutating your yeast.
