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Date: 07 Jun 2006 12:13:02
From:
Subject: oxygenating for secondary fermentation?
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I'm confused about wether to oxygenate my beer for secondary
fermentation or not. I use a 6 gallon glass carboy as primary and a 5
gallon glass as secondary. I was under the impression that if the
oxygen in the wort is all used up before the sugars are converted, then
oxygenating the beer while racking to the secondary can restart the
fermentation. Is this ture? Further more, how do I know if it is
needed? I assume it would only be neccesary for higher gravity beers.
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Date: 07 Jun 2006 20:29:22
From: Droopy
Subject: Re: oxygenating for secondary fermentation?
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Yes, in part, after the sugar level drops down to a certain percent
yeast will switch over to aerobic respiration and start metabolizing
the alcohol. It is their last ditch effort at staying alive. Now that
is also the final straw, as I will point out below.
Think about how yeast have evolved. Say a piece of fruit falls out of
a tree. there is all sorts of bacteria and other mocribes around. the
yeast has to compete. It starts out with alcoholic fermentation
becasue 1) it is fast 2) it produces a byproduct that many other
microbes cannot metabolize (and is actually toxic to them). Now the
yeast can metabolize alcohol. So after all the easy pickings have been
used up they can switch back and in the presence of oxygen utilize the
alcohol as an energy source.
That also means that if there is sugar around, yeast will strictly
undergo anaerobic metabolism and produce alcohol, whether there is
oxygen around or not. The amount of oxygen needed for yeast to
complete fermentation is fairly small. They use it mainly for sterol
synthesis and unsaturated fatty acid synthesis, which they need to
divide (they are part of their cell membranes)
Now (these are arbitrary amounts), say your yeast need 100 ppm of total
oxygen over the course of fermentation to reach optimal viability. If
you go nuts and give them 300 ppm they will actually use all of it, in
part they make excess sterols, and unsaturated fatty acids, saving up
so to speak. They also have some other minor metabolic pathways that
use oxygen. it seems almost that yeast given the chance will make
their environment anaerobic. They not only hog all the availabloe
sugar, they seem to sop up all the oxygen they can as well. Which
would make sense, in that way they could outcompete obligate aerobes
and also compete with facultative aerobes.
If yeast were not so good at what they do, humans would have had a hell
of a lot harder time making beer f(and wine and mead) or the last 8000
years or so.
nickstrachan wrote:
> Droopy wrote:
> > Metabolically as long as the yeast are active adding oxygen anytime
> > during fermentation will not HURT your beer, except maybe it might
> > reduce your ABV.
> >
> >
>
>
>
> Now Will this reduction in acohol occur because the yeast cells
> basically switch back to areobic fermentation/respiration(by product:
> co2 and other things as well as creating new cells) verses anerobic
> ( by product: acohol and other things and no new cells)
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Date: 07 Jun 2006 19:35:14
From: nickstrachan
Subject: Re: oxygenating for secondary fermentation?
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Droopy wrote:
> Metabolically as long as the yeast are active adding oxygen anytime
> during fermentation will not HURT your beer, except maybe it might
> reduce your ABV.
>
>
Now Will this reduction in acohol occur because the yeast cells
basically switch back to areobic fermentation/respiration(by product:
co2 and other things as well as creating new cells) verses anerobic
( by product: acohol and other things and no new cells)
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Date: 07 Jun 2006 14:46:09
From: Droopy
Subject: Re: oxygenating for secondary fermentation?
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Metabolically as long as the yeast are active adding oxygen anytime
during fermentation will not HURT your beer, except maybe it might
reduce your ABV.
In general it is not needed though. High gravity beers are another
matter, which all discussion that i have ever seen on adding more
oxygen after fermentation has started has been in reference to.
Now if there is no active yeast adding oxygen is a bad thing.
John 'Shaggy' Kolesar wrote:
> On 7 Jun 2006 13:20:04 -0700, <jasonkw62@hotmail.com> wrote:
> > Not exactly after it is over, but after it has ceased. When I started
> > brewing about 9 years ago I was taught by a master brewer (american
> > brewers guild) who owned the local shop. I was doing a high gravity
> > barley wine and he had me pitch champagne yeast and aerate into a
> > secondary after signs of fermentation had stopped. The fermentation
> > started again and finished. In a conversation with him he was saying
> > you could do that for other beers, but you would need to make sure it
> > will ferment more so that it strips the oxygen out of the beer.
>
> I would not recommend doing that as a general procedure. Except in the
> case where you know there is a stuck fermentation, there should be no need
> to re-aerate in the secondary in order to get the beer to finish fermenting.
> Even in the case where you do have a stuck fermentation, re-aerating will not
> always be the correct thing to do in order to solve it.
>
>
> John.
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Date: 07 Jun 2006 13:20:04
From:
Subject: Re: oxygenating for secondary fermentation?
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John 'Shaggy' Kolesar wrote:
> On Wed, 07 Jun 2006 12:43:11 -0700, <usenet@jamesrobert.us> wrote:
> > Now, you see this is interesting to me. I was reading yesterday or the
> > day before on Danstar's website I think. And it was a question and
> > answer forum and oxygenation came up. The featured expert said that in
> > his opinion oxygenating at pitch time was wrong and that it should
> > happen 24-48 hours into fermentation.
>
> I haven't heard that one before, it doesn't seem to make much sense.
>
> I've also seen opinions that say to aerate before you pitch the yeast and
> then to aerate 12-18 hours later.
>
> Whether or not you subscribe to those theories, both are completely different
> from what the OP was asking... IE do you need to aerate again when racking
> to a secondary (presumably several days later) after most fermentation
> activity is over.
>
> IMO, aerating before pitching only, aerating 24 hours after pitching, or
> doing some combination has to do with the original infusion of oxygen into
> the beer in order to support the reproduction of the yeast cells.
>
>
> John.
Not exactly after it is over, but after it has ceased. When I started
brewing about 9 years ago I was taught by a master brewer (american
brewers guild) who owned the local shop. I was doing a high gravity
barley wine and he had me pitch champagne yeast and aerate into a
secondary after signs of fermentation had stopped. The fermentation
started again and finished. In a conversation with him he was saying
you could do that for other beers, but you would need to make sure it
will ferment more so that it strips the oxygen out of the beer.
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Date: 07 Jun 2006 20:28:49
From: John 'Shaggy' Kolesar
Subject: Re: oxygenating for secondary fermentation?
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On 7 Jun 2006 13:20:04 -0700, <jasonkw62@hotmail.com > wrote:
> Not exactly after it is over, but after it has ceased. When I started
> brewing about 9 years ago I was taught by a master brewer (american
> brewers guild) who owned the local shop. I was doing a high gravity
> barley wine and he had me pitch champagne yeast and aerate into a
> secondary after signs of fermentation had stopped. The fermentation
> started again and finished. In a conversation with him he was saying
> you could do that for other beers, but you would need to make sure it
> will ferment more so that it strips the oxygen out of the beer.
I would not recommend doing that as a general procedure. Except in the
case where you know there is a stuck fermentation, there should be no need
to re-aerate in the secondary in order to get the beer to finish fermenting.
Even in the case where you do have a stuck fermentation, re-aerating will not
always be the correct thing to do in order to solve it.
John.
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Date: 07 Jun 2006 19:25:42
From: John 'Shaggy' Kolesar
Subject: Re: oxygenating for secondary fermentation?
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On 7 Jun 2006 12:13:02 -0700, <jasonkw62@hotmail.com > wrote:
> I'm confused about wether to oxygenate my beer for secondary
> fermentation or not. I use a 6 gallon glass carboy as primary and a 5
> gallon glass as secondary. I was under the impression that if the
> oxygen in the wort is all used up before the sugars are converted, then
> oxygenating the beer while racking to the secondary can restart the
> fermentation. Is this ture? Further more, how do I know if it is
> needed? I assume it would only be neccesary for higher gravity beers.
No, you do not want to aerate/oxygenate the wort after fermentation has
started. IMO, definitely do not oxygenate when racking to a secondary.
The only time I would even think about it is if I had a stuck fermentation
and had to pitch a new packet of yeast, even then I'd think twice if I could
fix it another way.
John.
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Date: 07 Jun 2006 12:43:11
From: Ryan Case
Subject: Re: oxygenating for secondary fermentation?
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John 'Shaggy' Kolesar wrote:
> On 7 Jun 2006 12:13:02 -0700, <jasonkw62@hotmail.com> wrote:
>> I'm confused about wether to oxygenate my beer for secondary
>> fermentation or not. I use a 6 gallon glass carboy as primary and a 5
>> gallon glass as secondary. I was under the impression that if the
>> oxygen in the wort is all used up before the sugars are converted, then
>> oxygenating the beer while racking to the secondary can restart the
>> fermentation. Is this ture? Further more, how do I know if it is
>> needed? I assume it would only be neccesary for higher gravity beers.
>
> No, you do not want to aerate/oxygenate the wort after fermentation has
> started. IMO, definitely do not oxygenate when racking to a secondary.
>
> The only time I would even think about it is if I had a stuck fermentation
> and had to pitch a new packet of yeast, even then I'd think twice if I could
> fix it another way.
>
>
> John.
Now, you see this is interesting to me. I was reading yesterday or the
day before on Danstar's website I think. And it was a question and
answer forum and oxygenation came up. The featured expert said that in
his opinion oxygenating at pitch time was wrong and that it should
happen 24-48 hours into fermentation.
I don't do anything other then the violent transfer from the boiler to
fermenter, but did think that what I had read seemed to go against
conventional brewing wisdom.
Ryan (who is going to continue to do things the way he has been, cause
he likes his results.)
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Date: 07 Jun 2006 19:55:23
From: John 'Shaggy' Kolesar
Subject: Re: oxygenating for secondary fermentation?
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On Wed, 07 Jun 2006 12:43:11 -0700, <usenet@jamesrobert.us > wrote:
> Now, you see this is interesting to me. I was reading yesterday or the
> day before on Danstar's website I think. And it was a question and
> answer forum and oxygenation came up. The featured expert said that in
> his opinion oxygenating at pitch time was wrong and that it should
> happen 24-48 hours into fermentation.
I haven't heard that one before, it doesn't seem to make much sense.
I've also seen opinions that say to aerate before you pitch the yeast and
then to aerate 12-18 hours later.
Whether or not you subscribe to those theories, both are completely different
from what the OP was asking... IE do you need to aerate again when racking
to a secondary (presumably several days later) after most fermentation
activity is over.
IMO, aerating before pitching only, aerating 24 hours after pitching, or
doing some combination has to do with the original infusion of oxygen into
the beer in order to support the reproduction of the yeast cells.
John.
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Date: 07 Jun 2006 20:10:59
From: John 'Shaggy' Kolesar
Subject: Re: oxygenating for secondary fermentation?
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On 7 Jun 2006 19:55:23 GMT, <spam@shagg.net > wrote:
> On Wed, 07 Jun 2006 12:43:11 -0700, <usenet@jamesrobert.us> wrote:
>> Now, you see this is interesting to me. I was reading yesterday or the
>> day before on Danstar's website I think. And it was a question and
>> answer forum and oxygenation came up. The featured expert said that in
>> his opinion oxygenating at pitch time was wrong and that it should
>> happen 24-48 hours into fermentation.
>
> I haven't heard that one before, it doesn't seem to make much sense.
I looked at Danstar's site to see if I could find the opinion you mentioned
since I was curious to see what their reasoning was, but could not find
anything about not oxygenating until 24-48 hours. Do you have a link?
John.
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Date: 07 Jun 2006 13:40:54
From: Ryan Case
Subject: Re: oxygenating for secondary fermentation?
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John 'Shaggy' Kolesar wrote:
> On 7 Jun 2006 19:55:23 GMT, <spam@shagg.net> wrote:
>> On Wed, 07 Jun 2006 12:43:11 -0700, <usenet@jamesrobert.us> wrote:
>>> Now, you see this is interesting to me. I was reading yesterday or the
>>> day before on Danstar's website I think. And it was a question and
>>> answer forum and oxygenation came up. The featured expert said that in
>>> his opinion oxygenating at pitch time was wrong and that it should
>>> happen 24-48 hours into fermentation.
>> I haven't heard that one before, it doesn't seem to make much sense.
>
> I looked at Danstar's site to see if I could find the opinion you mentioned
> since I was curious to see what their reasoning was, but could not find
> anything about not oxygenating until 24-48 hours. Do you have a link?
>
>
> John.
>
>
Sure,
And I will be the first to admit that I may have misunderstood the
question or answer. I also wasn't trying to be argumentative or
contradictory by any means. Just that the present conversation jogged my
memory of what I had read yesterday. And please, if I am confused, let
me know where. Like I said before, I don't plan on changing what I am
doing, because I am liking my results, but I like understanding and
having the knowledge to change too.
http://consumer.lallemand.com/danstar-lalvin/fortnightyeast.html#oxywort
Ryan (linked text to follow)
>--
>-- From: Bob Devine
>--
>-- Some British brewers "drop" their fermenting wort up to a day after adding yeast. How effective is this for adding oxygen? And how late can wort be oxygenated?
>--
>-- Response from Dr. Clayton Cone:
>-- The optimum time to add oxygen to the fermentation is about 12 - 24 hours into the fermentation.. Active Dry Beer Yeast(does) and re-pitched yeast (usually) have
>--enough lipids for two to three generations. It is at that time the budding yeast can most efficiently use the oxygen to continue to bud and also produce enough
>--lipids to protect itself against the higher levels of alcohol. This is especially true with high gravity brewing. In wine fermentation it is not uncommon to add oxygen
>--to a stuck fermentation near the end of the fermentation when there has been inadequate oxygen added at the beginning. The yeast will not grow but will metabolize the
>--oxygen to produce more lipids that will revive the elasticity or fluidity of the cell wall and allow the transport of the alcohol out of the cell to a safe lever and
>--then begin to transport sugar into the cell again.
>--
>-- Return to Top
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Date: 07 Jun 2006 21:11:44
From: John 'Shaggy' Kolesar
Subject: Re: oxygenating for secondary fermentation?
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On Wed, 07 Jun 2006 13:40:54 -0700, <usenet@jamesrobert.us > wrote:
> John 'Shaggy' Kolesar wrote:
>> On 7 Jun 2006 19:55:23 GMT, <spam@shagg.net> wrote:
>>> On Wed, 07 Jun 2006 12:43:11 -0700, <usenet@jamesrobert.us> wrote:
>>>> Now, you see this is interesting to me. I was reading yesterday or the
>>>> day before on Danstar's website I think. And it was a question and
>>>> answer forum and oxygenation came up. The featured expert said that in
>>>> his opinion oxygenating at pitch time was wrong and that it should
>>>> happen 24-48 hours into fermentation.
>>> I haven't heard that one before, it doesn't seem to make much sense.
>>
>> I looked at Danstar's site to see if I could find the opinion you mentioned
>> since I was curious to see what their reasoning was, but could not find
>> anything about not oxygenating until 24-48 hours. Do you have a link?
>>
>>
>> John.
>>
>>
>
> Sure,
>
> And I will be the first to admit that I may have misunderstood the
> question or answer. I also wasn't trying to be argumentative or
> contradictory by any means.
I didn't take it that way at all, it just raised my curiosity when you
mentioned oxygenating at pitch was wrong and to oxygenate at 24-48 hours
instead. I don't think that's exactly what the article said though. ;)
> Just that the present conversation jogged my
> memory of what I had read yesterday. And please, if I am confused, let
> me know where. Like I said before, I don't plan on changing what I am
> doing, because I am liking my results, but I like understanding and
> having the knowledge to change too.
Liking your results is, IMO, the most important part.
> http://consumer.lallemand.com/danstar-lalvin/fortnightyeast.html#oxywort
That kind of follows along the lines of the one forum post I did find earlier
where the question was specifically about high gravity worts, IE how to get
your yeast to ferment >12% ABV or 1.100 OG. Dr Cone basically said that
oxygen is even more important with high gravity beers and that in his opinion
if you do all of your oxygenation in the beginning then a lot of the O2
is wasted (he didn't explain how or why). He recommended that you add
at least some of the O2 at around 14 hours after pitching, since in his opinion
the yeast will be "hungry" for O2 again at that point.
Based on your link, I don't think he's saying not to oxygenate at all in the
beginning, I think what he's saying is that it can be beneficial to add O2
again at 14-24 hours, especially for beers that require higher levels or in
cases where inadequate oxygen was added originally. This is more in line with
other opinions I had heard which stated it was optimal to aerate in the
beginning and then again 12-18 hours later.
IMO, I don't think it's really necessary, although theoretically it might
help. In the case of a high OG beer, a combination of increasing the pitching
rate as well as doing an extra good job of aerating when you pitch should
be more than sufficient. IMO, the increased pitching rate goes a long way
towards reducing the yeast being O2 starved after 14-24 hours since the
amount of reproduction they are required to go through will be lower. Also,
making sure that you aerate enough during pitching will reduce the need to
aerate again. Where a second aeration at 14-24 hours might be beneficial
is for brewers that use aeration methods which are known for not being
very effective.
John.
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Date: 07 Jun 2006 19:11:49
From: Mike Undercofler
Subject: Re: oxygenating for secondary fermentation?
|
I pretty much agree with John here, but can add one sidebar to give some
credit for 12-24 hours idea.
A barleywine I made a few years ago blew the fermentation lock off about
16/18 hours after I had pitched. This was before I started to use a blowtube
for the first day or two of fermentation. (I like a lot of esters, hot and
fast primary.) As I was moving things around to clean up the mess, our cat
got under my feet. Not much got spilled, and the cat and I both escaped
without injury, but the beer got very *very* shook up to open air. It wound
up being one of the best barleywines I've ever made.
After reading this thread, and the info from the link you supplied, I think
the next time I make a barleywine, I'll try giving it some air after it has
started. Although, I think I'll skip the tripping over the cat part, and
just use a stainless wisk... should be much less mess to clean up that way.
Mike
--
Mike Undercofler
Howard, PA
Email: michael@**cut_from_stars_to_arrows >>mlux2.com
"John 'Shaggy' Kolesar" <spam@shagg.net > wrote in message
news:slrne8egan.52u.spam@weizen.shagg.net...
> On Wed, 07 Jun 2006 13:40:54 -0700, <usenet@jamesrobert.us> wrote:
>> John 'Shaggy' Kolesar wrote:
>>> On 7 Jun 2006 19:55:23 GMT, <spam@shagg.net> wrote:
>>>> On Wed, 07 Jun 2006 12:43:11 -0700, <usenet@jamesrobert.us> wrote:
>>>>> Now, you see this is interesting to me. I was reading yesterday or the
>>>>> day before on Danstar's website I think. And it was a question and
>>>>> answer forum and oxygenation came up. The featured expert said that in
>>>>> his opinion oxygenating at pitch time was wrong and that it should
>>>>> happen 24-48 hours into fermentation.
>>>> I haven't heard that one before, it doesn't seem to make much sense.
>>>
>>> I looked at Danstar's site to see if I could find the opinion you
>>> mentioned
>>> since I was curious to see what their reasoning was, but could not find
>>> anything about not oxygenating until 24-48 hours. Do you have a link?
>>>
>>>
>>> John.
>>>
>>>
>>
>> Sure,
>>
>> And I will be the first to admit that I may have misunderstood the
>> question or answer. I also wasn't trying to be argumentative or
>> contradictory by any means.
>
> I didn't take it that way at all, it just raised my curiosity when you
> mentioned oxygenating at pitch was wrong and to oxygenate at 24-48 hours
> instead. I don't think that's exactly what the article said though. ;)
>
>> Just that the present conversation jogged my
>> memory of what I had read yesterday. And please, if I am confused, let
>> me know where. Like I said before, I don't plan on changing what I am
>> doing, because I am liking my results, but I like understanding and
>> having the knowledge to change too.
>
> Liking your results is, IMO, the most important part.
>
>> http://consumer.lallemand.com/danstar-lalvin/fortnightyeast.html#oxywort
>
> That kind of follows along the lines of the one forum post I did find
> earlier
> where the question was specifically about high gravity worts, IE how to
> get
> your yeast to ferment >12% ABV or 1.100 OG. Dr Cone basically said that
> oxygen is even more important with high gravity beers and that in his
> opinion
> if you do all of your oxygenation in the beginning then a lot of the O2
> is wasted (he didn't explain how or why). He recommended that you add
> at least some of the O2 at around 14 hours after pitching, since in his
> opinion
> the yeast will be "hungry" for O2 again at that point.
>
> Based on your link, I don't think he's saying not to oxygenate at all in
> the
> beginning, I think what he's saying is that it can be beneficial to add O2
> again at 14-24 hours, especially for beers that require higher levels or
> in
> cases where inadequate oxygen was added originally. This is more in line
> with
> other opinions I had heard which stated it was optimal to aerate in the
> beginning and then again 12-18 hours later.
>
> IMO, I don't think it's really necessary, although theoretically it might
> help. In the case of a high OG beer, a combination of increasing the
> pitching
> rate as well as doing an extra good job of aerating when you pitch should
> be more than sufficient. IMO, the increased pitching rate goes a long way
> towards reducing the yeast being O2 starved after 14-24 hours since the
> amount of reproduction they are required to go through will be lower.
> Also,
> making sure that you aerate enough during pitching will reduce the need to
> aerate again. Where a second aeration at 14-24 hours might be beneficial
> is for brewers that use aeration methods which are known for not being
> very effective.
>
>
> John.
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