Conditioning a function of yeast or other chemical reactions?

[verysupple]

Point taken Mark, I maybe shouldn't have said in such absolute terms that maturation doesn't require yeast in suspension. But it's hard to say otherwise when many commercial beers are pasturised very soon (days rather than weeks) after reaching terminal gravity and definitely don't seem to need more maturation. In those cases active yeast in suspension isn't needed.

schrodinger I bet your a physicist or such like

Hahaha, actually I'm a physicist, :lol:

 

[MHB]

Oh well one point in parting.
Yes some commercial brewers pitch massive quantities, there was a thread a while ago where the head brewer from Budvar said they used 5L of heavy yeast slurry/HL, doing a bit of basic finger counting that's roughly 64 day old smack packs in 20L of wort.
If you are pitching those sort of quantities, primary will be over in a lot less than 7 days - even at 8oC, I promise. In the case of budvar 72 hours, note that they cooled to lagering tems over a couple of days with the yeast entrained with the beer. The luxury of having one of the worlds great lager yeasts as a waste product.

I've enjoyed this thread
Think I will go back into hibernation for a while, this place is just getting too nasty, tho this thread has been a bit of an exception.
Mark

 

[verysupple]

I've enjoyed this thread
Think I will go back into hibernation for a while, this place is just getting too nasty, tho this thread has been a bit of an exception.
Mark

Good to hear, Mark. I've been somewhat uninterested in most threads lately too. So when I had a question that I thought might instigate some deeper brewing related discussion I thought others might enjoy it too.

 

[manticle]

If you are conditioning your beer under gladwrap with a big airspace in a plastic fermenter the sooner you bottle it or keg it the better. If you have a good airtight glass or SS fermenter you can take your time and wait till you are happy with the flavour. A lot depends on your equipment. Bottle conditioning is a lot safer.

Glad wrap on beer is not as evil as you think it is. It's a balancing act for sure but 'sooner is better' is a little simplistic.

 

[wereprawn]

Point taken Mark, I maybe shouldn't have said in such absolute terms that maturation doesn't require yeast in suspension. But it's hard to say otherwise when many commercial beers are pasturised very soon (days rather than weeks) after reaching terminal gravity and definitely don't seem to need more maturation. In those cases active yeast in suspension isn't needed.


Hahaha, actually I'm a physicist, :lol:

As a physicist, I was waiting for you to advise Schrodinger not to observe or measure the beer so he could have each yeast cell alive and dead at the same time. :lol: :blink:

 

[schrodinger]

schrodinger I bet your a physicist or such like

...don't leave beer - under any conditions - on the primary yeast cake for more than two weeks

Biologist, actually! (but with physics envy :lol: )

But Mark, whether the issues arise from yeast murder, suicide, or self-mutilation, it seems like racking off the cake wouldn't have any effect -- either the chemistry in question is happening in a mm or two above the cake (in which case it would have negligible effect on the beer whether you rack or not) or it's happening throughout the beer due to activity of yeast still in suspension (in which case it will follow the beer with racking).

Early on, I always racked ASAP to avoid overexposure to old and/or dead yeast, based on advice like this. At some point I stopped, but have never noticed any consequences.

 

[Greg.L]

Glad wrap on beer is not as evil as you think it is. It's a balancing act for sure but 'sooner is better' is a little simplistic.

My point is that decisions about conditioning on the yeast should be influenced by the fermentation container. If you are using a container with high O2 permeability and high surface area/volume ratio, you shouldn't leave it in that container very long because the beer will oxidise and deteriorate fairly rapidly, also a risk of infection caused by the presence of Oxygen. This is partly why professionals spend money on good quality fermenters, it gives them more options.

 

[Yob]

If you are using a container with high O2 permeability and high surface area/volume ratio, you shouldn't leave it in that container very long because the beer will oxidise and deteriorate fairly rapidly

How long is 'very long' ? What sort of surface area are we talking? How big a tank? what is the magical surface area/volume ratio cutoff point? are you talking beer or Cider and Wine?


Details please..

 

[verysupple]

Biologist, actually! (but with physics envy :lol: )

But Mark, whether the issues arise from yeast murder, suicide, or self-mutilation, it seems like racking off the cake wouldn't have any effect -- either the chemistry in question is happening in a mm or two above the cake (in which case it would have negligible effect on the beer whether you rack or not) or it's happening throughout the beer due to activity of yeast still in suspension (in which case it will follow the beer with racking).

Early on, I always racked ASAP to avoid overexposure to old and/or dead yeast, based on advice like this. At some point I stopped, but have never noticed any consequences.

It may only affect the first 1 mm or so initially, but my understanding of statistical mechanics leads me to think that given enough time the molecules would not remain only in the bottom 1 mm or so. I'd suggest another reason as to why you never noticed a difference when you started not racking ASAP, You're probably still not leaving it long enough for a significant amount of autolysis or catabolism to occur. My understanding is that if the yeast were in pretty good health at the end of fermentation then it will take a fair while (at fermentation temps, you don't want to warm it up to 50 C or anything) before anything too untoward will rear it's head.

In the end I think there's a lot of leeway when it comes to when you can separate the beer from the yeast. You certainly can remove the yeast too soon or too late, but I think there's usually a good few weeks inbetween where you're pretty safe.

Essentially I wanted to know how early was too early. And the consensus seems to be if there isn't any diacetyl, acetaldehyde or other unwanted compounds that the yeast can actually metabolise into something less disagreeable (these are usually dealt with by the time you reach terminal gravity or in the first couple of days thereafter), then it's fine separate.

EDIT:
PS. Greg.L has argued and explained his idea behind the whole gladwrap/oxidation/infection thing in this thread starting at post #13. I think it's going a bit too OT for here.
http://aussiehomebrewer.com/topic/75340-why-are-you-getting-infected/

 

[technobabble66]

Fwiw,
My *single* experience w long primary fermentation was 6 weeks on a pale ale and the 2013 July case swap stout.
Both turned out brilliantly, IMHO.
The ale was particularly clean & smooth (done w a kolsch yeast, if that makes a difference); the only problem I had was carbing them in the bottle, as the yeast had gotten lazy & took some shaking to get going over several weeks.
I'll get Manticle to taste test both soon, if possible, to confirm I haven't missed anything, but I was pleasantly surprised with the results.
Obviously this is a tiny sample size, the stout in particular could mask bad flavours, and is not "significant"; but I just thought I'd put it out there that 6 weeks in a plastic fermenter (at ~18*C) may occasionally be ok ... or that miracles do indeed occur.

 

[Greg.L]

How long is 'very long' ? What sort of surface area are we talking? How big a tank? what is the magical surface area/volume ratio cutoff point? are you talking beer or Cider and Wine?


Details please..

There are no exact answers, that is where the skill lies - working out what is the best solution for the job. I was specifically talking of beer; I used to make beer in a 25L plastic bucket with a snap-on lid. That was the fermenter I had and it did a reasonable job, but I would only leave the beer in there for a maximum of 3 weeks, usually less. The fermentation would finish in a few days, then a week or two for the beer to drop clear (ish). If you want to get more technical with cooler longer fermentation and a month or 2 of conditioning, then you would be foolish to use a plastic bucket, you need to take more care to keep the oxygen out if you are taking more trouble in other areas. If you want to make a better product then you need to take make more effort in all areas, getting a better fermenter is one easy way of improving your operation.

 

[Yob]

So for example, an Ale/IPA that's finished in a week or less, another 4 days to clean up... no biggie, what you are really discussing with oxidization really relates to long term issues rather than the short time frame usually encountered on a HB scale with anything other than lagers.

Agreed that if I was lagering (which I dont do generally) Fermenting in a conical may well be better (over a longer time frame)... then transfer to keg for lagering.. is probably something I would look at.. but isnt really essential for most, plenty of prise winners out there that have come from a plastic tub... probably even with gladwrap.

 

[wobbly]

From what I have read in this topic the arguments seem to be about "How long to leave the fresh beer on the yeast to allow it to "Clean it up" or alternatively "How long to lager the beer for to again "clean it up" or tame off/harsh flavours".

Now I'm not going to suggest that those who have written/been quoted as authorities on this subject are not up to date with modern brewing practices but there seems to be something worth taking note of in the "process" of fermenting under CO2 pressure and the Clarification phase associated with the Williamswarn system

Closed fermentation (CO2 pressure) is stated in a number of papers to be a faster process that produces significantly less/minimal "off flavours" requiring removal either by time on the yeast cake or some sort of maturation period

The Williamswar process (not necessarily the machine) of CO2 pressure fermentation, Oxygen free environment, 24-36hrs clarification phase, also seems to achieved what those using "open fermentation processes" require extended time through longer exposure to the yeast and/or a maturation period of a couple of weeks

Now I don't wish the above to be seen as another attempt by me to "push" the Williamswarn machine but an opportunity to seriously consider the "process" they have adopted and how it may enhance faster and improved production of beer in the home

Maybe this should have been posted in the "Pressure Fermenting" topic but I have chosen this topic as it is considered more relevant to my comments

Cheers

Wobbly

 

[verysupple]

From what I have read in this topic the arguments seem to be about "How long to leave the fresh beer on the yeast to allow it to "Clean it up" or alternatively "How long to lager the beer for to again "clean it up" or tame off/harsh flavours".

Now I'm not going to suggest that those who have written/been quoted as authorities on this subject are not up to date with modern brewing practices but there seems to be something worth taking note of in the "process" of fermenting under CO2 pressure and the Clarification phase associated with the Williamswarn system

Closed fermentation (CO2 pressure) is stated in a number of papers to be a faster process that produces significantly less/minimal "off flavours" requiring removal either by time on the yeast cake or some sort of maturation period

The Williamswar process (not necessarily the machine) of CO2 pressure fermentation, Oxygen free environment, 24-36hrs clarification phase, also seems to achieved what those using "open fermentation processes" require extended time through longer exposure to the yeast and/or a maturation period of a couple of weeks

Now I don't wish the above to be seen as another attempt by me to "push" the Williamswarn machine but an opportunity to seriously consider the "process" they have adopted and how it may enhance faster and improved production of beer in the home

Maybe this should have been posted in the "Pressure Fermenting" topic but I have chosen this topic as it is considered more relevant to my comments

Cheers

Wobbly

Yes, I think it is reasonably well documented that fermenting under pressure is a complete game changer. However there are still commercial breweries out there using pretty much every method you can think of. Capped vessel, open vessel, short and wide, tall and skinny...They all have an effect. It still seems, though, that they don't need the weeks and weeks at fermenting temps on the bulk yeast mass, such as a lot of homebrewers here advocate, to produce bood beer. Some comercial brewers do use a warm maturation, but for days rather than weeks and only with the suspended yeast, they usually remove the beer from the bulk of the yeast which has flocculated.

So you can make "clean" beer using pretty much any of the usual fermenting conditions. The fermenting conditions (typically defined by the equipment on a homebrew scale) will have an effect on the processes a brewer may have to use to achieve the desired product. But again, I think if you need weeks and weeks of contact with the yeast for every batch you brew, you're probably doing something wrong upstream.