I have been trying to figure out why people say the beer has to be on the yeast cake for them to do there job. Things like you transferred to early or it did not have time to condition properly. When the yeast fall out of suspension, arent they not active anymore? When you transfer to a keg or secondary and leave it at room temperature, the yeast are still working. I can see if you filter, use finings, or cold temperature that this would not be the case, but I have wondered if the yeast cake on the bottom is still active. Please discuss.
Yeast in suspension and yeast cake
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Actually. This is the MOST discussed topics on here, already. There are literally THOUSANDS of threads discussing, debating, arguing, and explaining. There's nothing we can discuss that will be any different than has already been discussed on here.
My suggestion, rather than re-invent the wheel is to read what's on here already.
May I suggest that you read this thread which pretty much is the most up to date discussion of the topic on here.
To Secondary or Not? John Palmer and Jamil Zainasheff Weigh In.
I don't want to come off rude...but really there's no need to beat this already dead horse any more. Just really spend some time reading that thread, and you will find all you need, to make up your own mind about this topic. Read it in it's entirity and you'll know everything you need to and more.
My real suggestion is to stop thinking about it or reading about it, just try each way on your next two batches of beer, Secondary one, primary another for a month. And come to your own conclusions.
andrew300
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My question wasn't about to secondary or not. I have read every one of those threads and read how to brew and the new yeast book numerous times. I was just trying to figure out if the yeast at the bottom have anything to do with the yeast in suspension in the beer. My thought is if I transfer it to a keg and store it in the closet for conditioning, I could have more room in my freezer to do fermentations. Instead of having to wait 4 weeks on the primary yeast cake. Not anything to do about secondaries as I don't even own one and have no intention to.
But what you asked about yeast contact IS in there. That's the whole point of the discussion. Maximum or minimum amount of yeast contact.
andrew300
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Am I wrong to say that the yeast that are in suspension are the ones that are reducing and creating compounds? Not the ones that have flocculated and are inactive? So if I understand correctly, there should be the same amount of yeast contact on the yeast cake versus not? I understand if you rouse or change the temperature of the beer on the yeast cake that they could go back into suspension.
I agree with your theory- that it's the active yeast that do most of the "work" and not the flocculated yeast at the bottom. However, I think it would vary from strain to strain. Some strains are notorious for being early flocculators, and will flocculate out before they are finished fermenting. Rousing the yeast helps, but those yeast are not dormant, just flocculated early. Some yeast strains are pretty non-flocculating and I am guessing that those are the ones that can be racked earlier without detrimental effect.
Keep in mind one thing, though. That once fermentable sugars are gone, the yeast go back and "clean up" some of their own by-products. Like diacetyl- they actually produce diacetyl early in fermentation, and then go back and digest it after the fermentable sugars are gone. In order for that to be fully effective, you need to have a) the fermentable sugars gone (by the yeast) and b) enough active yeast to do the job. By racking early, you could set back that process, because even if if there are still yeast in suspension you might get the "laziest", least flocculant yeast.
I haven't read any research on this, so it would be awesome if there were some studies about this. All I know is anecdotal evidence, that my beers are clearer and cleaner tasting after a long primary.
? Rev, you got so lost in your reply you forgot his question.
Anyhoo, to the point, it seems that the flavor of the beer can change dramatically over time when left on the yeast. Not only are many of the "off" flavors fixed, but the overall quality of the beer improves.
I agree, this seems odd, since the yeast seems to fall hard, inactive, after a week of active fermentation. I can't resolve this obvious contradiction except to say to trust the yeast, it'll get the job done.
andrew300
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Yeah it would be interesting to know what type of impact, if any that you would get from staying on the yeast cake versus transferring and keeping the temperature the same for conditioning. I would think it is the ones in suspension that are doing most of the clean up. If this were the case, I could transfer the beer to the numerous amount of kegs I have and free up my primary fermenter, which I only have 1 of. I guess this would act as a secondary, but it could go straight to the kegerator after conditioning instead of being exposed to more oxygen in another transfer like a secondary carboy would.
My guess would be that the yeast cake is apart of things during the beginning of fermentation, kinda being in equilibrium with the suspended yeast during the respiration and beginning fermentation stages. So, I don't think you could transfer a beer every day (off the cake) to a diff. container during fermentation and expect to get full attenuation. Purely my opinion (plus it would at lot of work to do that!)
I personally think that once fermentation is complete (which can take a wide range of days depending on many factors, temp., yeast strain, OG, etc.) then the yeast that is still in suspension is capable of cleaning up what the flocculated yeast has produced (the by-products).
Leaving the beer in the primary longer is more of a safety net approach. A "lets just leave it alone" approach. Siphoning off the yeast cake post-fermentation to a secondary/keg will bring a ton of yeast with it (this is why you can bottle condition beers). That suspended yeast is plenty capable of cleaning up the beer.
There, I discussed.
I personally think that once fermentation is complete (which can take a wide range of days depending on many factors, temp., yeast strain, OG, etc.) then the yeast that is still in suspension is capable of cleaning up what the flocculated yeast has produced (the by-products).
Leaving the beer in the primary longer is more of a safety net approach. A "lets just leave it alone" approach. Siphoning off the yeast cake post-fermentation to a secondary/keg will bring a ton of yeast with it (this is why you can bottle condition beers). That suspended yeast is plenty capable of cleaning up the beer.
There, I discussed.
Basically. Remember, lagering/conditioning is a physical phenomenon. Sedimentation is the main process occurring, that's why close to freezing temps are recommended. The yeast isn't active at that temp, but the colder temperature promotes flocculation, which results in faster sedimentation.
The point of lagering is to get yeast out of suspension = clean tasting lagers
Well, no. Remember that in a conical, you can dump yeast all the time. Even using gelatin and lagering, yeast remain in suspension. I've lagered for 4 months, and still had carbonation from the yeast in susupension.
And some strains are non-flocculant, while others are very flocculant. And still the beer conditions.
Some lager strains will continue working at low temperatures, that's why the temperature is dropped slowly instead of cold crashing a lager. There are so many different things going in in lager- reduction of polyphenols for one, that it's not really a good comparison to leaving an ale in primary vs lagering. Remember that lagering is done once the beer is racked off of the yeast cake.
Well of course there is still yeast in suspension. I didn't say it ALL drops out, just that it PROMOTES the sedimentation of the suspended particles (e.g. the yeast and its by-products).
Non-flocculating and flocculating is a relative term for how the yeast behaves within the boundaries of how yeast works in beer. So, a "flocculating" yeast is simply MORE flocculant that a "non-flocculating". That doesn't mean its going to drop out of suspension 100% (because then it wouldn't make wort into beer to human standards).
There is a Brew Strong Podcast about lagering or using a secondary (can't remember the exact topic). You should give it a listen if you can get past 50% idle banter of the hour+ program.
Non-flocculating and flocculating is a relative term for how the yeast behaves within the boundaries of how yeast works in beer. So, a "flocculating" yeast is simply MORE flocculant that a "non-flocculating". That doesn't mean its going to drop out of suspension 100% (because then it wouldn't make wort into beer to human standards).
There is a Brew Strong Podcast about lagering or using a secondary (can't remember the exact topic). You should give it a listen if you can get past 50% idle banter of the hour+ program.
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This may be true, but is counterintuitive. It makes more sense that flocculate yeast are the lazy ones because they dropped before the job was done and the yeast still in suspension are the guys still at work.
Good point- but perhaps it's the "slowest" least flocculant yeast still in suspension and the hardest workers are done? It's just a thought I had. Definitely NOT scientific in origin!
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So, in running terms, the flocculate yeast are the 100 meter guys. They sprint out, consume all the glycogen in their muscles and drop on the track at the end of the straightaway. The yeast still in suspension are the milers who pace their energy supply for four loops of the track.
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But not implying that either one is bad or better than the other. Just that both skills have their place.
In some situations, lasting longer is a good thing. Certainly not lazy!
But the Pacman family are doing such a good job. Someone has to speak in their behalf.
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