Hungry yeast vs. lower attenuation yeast; achieving body

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GuitarGumption

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I have had this question in the back of my mind for a bit. So lets say I wanted to make a brew with about 1.060 OG, and wanted to finish it around 1.015.All other things being equal, what would be different about the beer if I used a yeast that naturally had the right attenuation to bring the beer to that point vs. using something like 3711 that would normally bring it much lower, and say, cold crashing the beer when it hit 1.015. And lets assume for time being that the yeasts had similar flavor profiles normally besides being drier or less dry.

Does this make sense?
 
GuitarGumption said:
I have had this question in the back of my mind for a bit. So lets say I wanted to make a brew with about 1.060 OG, and wanted to finish it around 1.015.All other things being equal, what would be different about the beer if I used a yeast that naturally had the right attenuation to bring the beer to that point vs. using something like 3711 that would normally bring it much lower, and say, cold crashing the beer when it hit 1.015. And lets assume for time being that the yeasts had similar flavor profiles normally besides being drier or less dry.

Does this make sense?

It makes sense but there is so much more involved in getting yeast to attenuate where you want: temperature, mash temp, grain bill, pitch rate, etc.

You could make two identical recipes and mash 3-5 degrees apart, pitch identical yeast and rate and get 2 different final gravity readings as an example.
 
Yes, but that's my point. With a yeast like 3711 you could mash almost anywhere between 148 and 158 and it would still bring your FG down super low if you didn't stop it. So what if you were loosy goosy about your mash temps and grain bill, but just used something like 3711 and kept a close eye on where your gravity was, and cold crashed it when it hit where you wanted it. How would this affect the final beer vs. controlling the gravity via mash temp, yeast rate, etc. ?
 
Yes, but that's my point. With a yeast like 3711 you could mash almost anywhere between 148 and 158 and it would still bring your FG down super low if you didn't stop it. So what if you were loosy goosy about your mash temps and grain bill, but just used something like 3711 and kept a close eye on where your gravity was, and cold crashed it when it hit where you wanted it. How would this affect the final beer vs. controlling the gravity via mash temp, yeast rate, etc. ?

Mashing at different temperatures changes the FG in that more non-fermenting sugars are produced at higher mash temperatures. It won't matter what the yeast is, if there's nothing for it to go through. Attenuation level only accounts for part of the FG calculations. Unless you're using a blended pack that includes yeast AND bacteria (bret) it will only go through the sugars it can. Produce more sugars that it can't, by mashing higher, and the FG WILL be higher.
 
Golddiggie said:
Mashing at different temperatures changes the FG in that more non-fermenting sugars are produced at higher mash temperatures. It won't matter what the yeast is, if there's nothing for it to go through. Attenuation level only accounts for part of the FG calculations. Unless you're using a blended pack that includes yeast AND bacteria (bret) it will only go through the sugars it can. Produce more sugars that it can't, by mashing higher, and the FG WILL be higher.

+1
Very off topic, but the mash paddles in your avatar are incredible. That knotwork makes my Irish side proud. I need one of those!
 
Lets try this again. I understand how mash temps affect fermentable sugars.

So say I brew the exact same process. The first one I use a lower attenuation yeast, such as say 65% (number doesn't matter).

I write down the final gravity. Say it's 1.018.

Second batch, same process. I use a high attenuation yeast. Say 90%.

I carefully watch fermentation and cold crash when gravity hits 1.018.

How would these two batches differ in flavor? Would the only difference be from the yeast profiles? Or is there some other reason that it is bad to crash a fermentation before the yeast has reached it's natural attenuation?

From what I've read it could be bad first of all because the yeast doesn't have time to clean up some of it's own products of fermentation...
 
IMO, it's a bad idea to try and stop yeast before they're fully done with the wort. Besides it would be very difficult to actually stop them as you describe. Since the yeast will do additional things with the beer after fermentation is complete, you really don't want to do that.

As for different flavors, you'll get that from using different yeasts with different spec's.
 
Forcing the yeast to stop is different than your original hypothesis and question:)

I'm in agreement that you allow the yeast to do their job and manipulate desired attenuation by mash temp. Also agree that if different flavors are desired you select different yeast or for that matter alter your fermentation temperature.

If you force yeast to stop doing their job and leave fermentables, once the Tempe rises back to a workable level, fermentation will start up again and possibly cause problems in what you assumed to be a finished product
 
Can you say BOTTLE BOMBS!!! I think you can, or you will if you try that out (forcing the yeast to stop before it's done). :eek:

At best, you would need to chemically stop the yeast, which means you'll have unfinished beer. With all the yeast does post fermentation, you'll end up with a lower quality product. IMO, not worth doing in that case.
 
Forcing the yeast to stop is different than your original hypothesis and question:)

I'm in agreement that you allow the yeast to do their job and manipulate desired attenuation by mash temp. Also agree that if different flavors are desired you select different yeast or for that matter alter your fermentation temperature.

If you force yeast to stop doing their job and leave fermentables, once the Tempe rises back to a workable level, fermentation will start up again and possibly cause problems in what you assumed to be a finished product

^^ This. It is very hard to stop a fermentation. The only way would be sterile filtration or pasteurization.
 
^^ This. It is very hard to stop a fermentation. The only way would be sterile filtration or pasteurization.

Two things. @duboman, this was exactly my original question if you read it carefully.

@others, it seems easy to stop fermentation by mistake ;) But seriously, if you cold crash and then transfer to secondary after the yeast has settled to the bottom, won't that mostly stop fermentation? And I don't use bottles, so bottle bombs is a non-issue for me. If it starts carbing up on it's own, that's less c02 I have to use...

I'm still not saying I want to do this, just doing a thought experiment for my own understanding of some things.
 
GuitarGumption said:
Two things. @duboman, this was exactly my original question if you read it carefully.

@others, it seems easy to stop fermentation by mistake ;) But seriously, if you cold crash and then transfer to secondary after the yeast has settled to the bottom, won't that mostly stop fermentation? And I don't use bottles, so bottle bombs is a non-issue for me. If it starts carbing up on it's own, that's less c02 I have to use...

I'm still not saying I want to do this, just doing a thought experiment for my own understanding of some things.

The problem I see is your understanding of attenuation as it is not a fixed certainty, it is a percentile range. Just because a yeast says it will attenuate to 70% does not mean it will as there are other factors in play such as mash temps and ferment ability.

In addition, yes by cold crashing and forcing the yeast to drop you are possibly halting fermentation there is still yeast in suspension to some degree so my prior concerns stated still are in play. I cold crash my beers to help clear but when I bottle I do not re-add yeast to carbonate and they always do showing that there is still enough yeast in the beer to do the job.

While you state that this may help carbonate without fear of bottle bombs, its just not true as you are dealing with a relatively unknown value of fermentable sugar remaining in the unfinished beer versus a calculated amount of added sugar in a finished beer.

As for kegging, you carbonate to a known/desired volume. If you keg and force a beer that is not finished, while the keg may not explode the beer will ultimately become way over carbonated if the beer begins fermenting again while tapped or un-tapped so it still should be a concern:)
 
Two things. @duboman, this was exactly my original question if you read it carefully.

@others, it seems easy to stop fermentation by mistake ;) But seriously, if you cold crash and then transfer to secondary after the yeast has settled to the bottom, won't that mostly stop fermentation? And I don't use bottles, so bottle bombs is a non-issue for me. If it starts carbing up on it's own, that's less c02 I have to use...

I'm still not saying I want to do this, just doing a thought experiment for my own understanding of some things.

Assuming you mean to say you keg. IMO, stopping the yeast before it's done it's job is just unwise. For one thing, you'll have off-flavors present that wouldn't be IF you had let it finish it's job. Post fermentation, the yeast cleans up the off by-products it created during fermentation. Stopping that from happening is beyond unwise.

IMO/IME, you're better off just making better yeast selections and doing what's needed to get the best performance from them.
 
Taste the beer and decide for yourself. If it tastes wrong finish fermentation. I'm certainly curious about the results.
 
Assuming you mean to say you keg. IMO, stopping the yeast before it's done it's job is just unwise. For one thing, you'll have off-flavors present that wouldn't be IF you had let it finish it's job. Post fermentation, the yeast cleans up the off by-products it created during fermentation. Stopping that from happening is beyond unwise.

IMO/IME, you're better off just making better yeast selections and doing what's needed to get the best performance from them.

Is this really the case? I cold crash and keg my cider before fermentation is complete. There are no off-flavors. Fermentation does not restart.

Pro brewers stop fermentation at desired FG all the time. Pretty standard practice.
 
Is this really the case? I cold crash and keg my cider before fermentation is complete. There are no off-flavors. Fermentation does not restart.

Pro brewers stop fermentation at desired FG all the time. Pretty standard practice.

Not familiar with cider so I cannot comment but I know several pro brewers out there and this is the first I hear of stopping fermentation as "standard practice"

I'm not saying that there aren't those that do but I'm sure they are doing it in such a way that they are ensuring there is no possibility of re-start. All those I know have great control and consistency over fermentation and attenuation to ensure quality control and consistency of product.

As for Goldiggie's comment, I'm sure he meant that if there were problems or issues with proper fermentation control there would be no chance for proper cleanup, not in all fermentation cases.

As an example of the concerns stated, there are plenty of threads on HBT about people that had stuck fermentations and they assumed the process was complete only to wind up with exploding bottles or well-overcarbonated beers because fermentation started up again.
 
Pro breweries have TIGHT temperature control over their fermentations. Something not a lot of home brewers have. Sure, there are people with fermentation chambers, but you'll find threads/posts from people still having temperature control issues. You also have people posting about off flavors that they are trying to trouble shoot.

IMO, it's better to properly design the recipe to get what you want than try to halt things mid-process. If you're kegging it, then you'll HAVE to keep the keg cold until it kicks. Not always an issue, but if you want to put something else in it's place before it kicks you can easily have issues. I'd rather properly design a recipe to give me what I want and let the yeast do as it needs.

I would also not advise doing this with any yeast you don't have extensive experience with. I'm talking about more than a few batches with the strain, over a variety of conditions and in more than one recipe.
 
Not familiar with cider so I cannot comment but I know several pro brewers out there and this is the first I hear of stopping fermentation as "standard practice"

Pro breweries have TIGHT temperature control over their fermentations. Something not a lot of home brewers have. Sure, there are people with fermentation chambers, but you'll find threads/posts from people still having temperature control issues. You also have people posting about off flavors that they are trying to trouble shoot.

IMO, it's better to properly design the recipe to get what you want than try to halt things mid-process. If you're kegging it, then you'll HAVE to keep the keg cold until it kicks. Not always an issue, but if you want to put something else in it's place before it kicks you can easily have issues. I'd rather properly design a recipe to give me what I want and let the yeast do as it needs.

I would also not advise doing this with any yeast you don't have extensive experience with. I'm talking about more than a few batches with the strain, over a variety of conditions and in more than one recipe.

Fullers does it. It's not hard...it might take you a few tries to get it perfect. Let's say you want it to stop at 1.015, try crashing it at 1.020. The only special equipment required is a refrigerator.

There are many ways to prevent a restart. Sure, keep it cold. Or you can use campden tabs, or you can filter, or you can pasteurize.

Lastly, you can't properly design a recipe that accomplishes what the OP is trying to accomplish through ingredients or mash temp alone. The guy wants to experiment. Don't discourage him. If it doesn't turn out perfect, who cares?
 
Fullers does it. It's not hard...it might take you a few tries to get it perfect. Let's say you want it to stop at 1.015, try crashing it at 1.020. The only special equipment required is a refrigerator.

There are many ways to prevent a restart. Sure, keep it cold. Or you can use campden tabs, or you can filter, or you can pasteurize.

Lastly, you can't properly design a recipe that accomplishes what the OP is trying to accomplish through ingredients or mash temp alone. The guy wants to experiment. Don't discourage him. If it doesn't turn out perfect, who cares?

With those 'prevention' methods, you are then forced to keg the brew. Not always an issue, but it can be for more than a few brewers. Filtering and pasteurizing have their own pitfalls associated. Campden tablets would be adding a chemical to try to stop what's going on. Which could introduce other off flavors.

Not saying to not do it, just saying (IMO) it's more trouble than it's worth. Also, don't expect any empathy/sympathy from me (and others I'm sure) when it goes sideways and the OP posts about having issues associated with doing this.

Oh, and IME, you CAN design a brew to give you what you really want. Including the body level with flavor profile without having to try and stop the yeast before it goes too far. PROPER yeast selection is one important item that very many home brewers fall flat on. They simply go with one (often dry) yeast for everything without thinking. Using different mash temperatures, malts, GU:BU ratios CAN give you what you want without having to chemically halt yeast, cold crash before the yeast is done, etc. IME/IMO cutting corners is rarely going to give you what you want, or something really good/great.
 
It is very difficult to stop a fermentation. That is why wine makers let wine ferment dry then back sweeten using Sorbistat K (Potassium Sorbate) and Kmeta (Potassium metabisulfite). If you just cold crash you have a biologically unstable product. You should always strive for stability in three area: 1) microbial, 2) cold, 3) heat

For microbial you want complete fermentation, very low residual nutrients, proper sanitation and if required, sanitary filtration and pasteurization.

The only way to stop an ACTIVE fermentation PERMANENTLY is to kill the yeast. Once fermentation is complete, you can prevent a restart with added fermentables by using Sorbate and Kmeta. Or you can get real fancy and use an encapsulated yeast product that can be removed when the desired attenuation is achieved. This is generally a winemaking technique since I don't think there are any encapsulated beer yeast products.
 
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