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General Category => Yeast and Fermentation => Topic started by: Lazy Ant Brewing on October 19, 2016, 01:47:56 PM

Title: Timing question regarding secondary fermentation
Post by: Lazy Ant Brewing on October 19, 2016, 01:47:56 PM
If you are racking from primary to secondary because you are adding ingredients to the secondary, does fermentation need to be completely finished before you do that?

My thought would be that the purpose of racking to the secondary is to leave most of the traub behind.  If this is the case, I'm thinking I could probably do that after perhaps 7 days and then leave the beer in there until fermentation is complete. Also, I don't care if some traub remains.  I bottle and most of the visible crud will settle to the bottom anyway.

If more info helps, I'm making a stout. fermenting with US05, and will be adding chocolate nibs and cinnamon sticks. 

Thanks in advance for your advice.
 
Title: Re: Timing question regarding secondary fermentation
Post by: HoosierBrew on October 19, 2016, 01:58:43 PM
If you are racking from primary to secondary because you are adding ingredients to the secondary, does fermentation need to be completely finished before you do that?

My thought would be that the purpose of racking to the secondary is to leave most of the traub behind.  If this is the case, I'm thinking I could probably do that after perhaps 7 days and then leave the beer in there until fermentation is complete. Also, I don't care if some traub remains.  I bottle and most of the visible crud will settle to the bottom anyway.

If more info helps, I'm making a stout. fermenting with US05, and will be adding chocolate nibs and cinnamon sticks. 

Thanks in advance for your advice.
 



Personally, I wouldn't transfer to secondary to use cocoa nibs and cinnamon. I'd wait until you reach FG, then add those ingredients in a fine mesh bag. Sample everyday or two and pull the bag when the flavor is where you want, then bottle/keg.
Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 20, 2016, 11:56:25 AM
Two schools of thought. Throw additions in the primary if you are worried about contamination. Or wait until fermentation is about 70% done and rack onto the fruit this adds a little more O2 but the yeast will use that and the fermentation should stop so the o2 will be scrubbed fairly fast IMO. If you wait for fermentation to stop before you transfer you will have to wait for it to start up again. Wine makers transfer actively fermenting wine all the time.
Title: Re: Timing question regarding secondary fermentation
Post by: JJeffers09 on October 20, 2016, 08:02:07 PM
I will say wine is not beer.  There is really a bigger risk of damaging your product if you transfer mid fermentation.  There is nothing worse than an under attenuated beer in my experience with transferring early.  If your beer stalls at 75% you wouldn't be happy, and you could get oxidation in your bottle/keg.  No Bueno.  I am with Jon, no absolute need to do it.  Although I am sure almost all of us have done it before.
Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 20, 2016, 10:13:03 PM
Fermentation won't stall. Under aerated beer will stall. Ever add dry hops after 5 days? It starts fermenting again from the oxygen that gets in with the hops. The risk of oxidation comes after fermentation is complete. At least that's what I believe. But like I said if you're worried just toss it in the primary.
Title: Re: Timing question regarding secondary fermentation
Post by: brewinhard on October 20, 2016, 11:22:14 PM
If you are racking from primary to secondary because you are adding ingredients to the secondary, does fermentation need to be completely finished before you do that?

My thought would be that the purpose of racking to the secondary is to leave most of the traub behind.  If this is the case, I'm thinking I could probably do that after perhaps 7 days and then leave the beer in there until fermentation is complete. Also, I don't care if some traub remains.  I bottle and most of the visible crud will settle to the bottom anyway.

If more info helps, I'm making a stout. fermenting with US05, and will be adding chocolate nibs and cinnamon sticks. 

Thanks in advance for your advice.
 



Personally, I wouldn't transfer to secondary to use cocoa nibs and cinnamon. I'd wait until you reach FG, then add those ingredients in a fine mesh bag. Sample everyday or two and pull the bag when the flavor is where you want, then bottle/keg.

I tend to lean towards this...

  If your beer stalls at 75% you wouldn't be happy, and you could get oxidation in your bottle/keg. 

How would this lead to oxidation?

Title: Re: Timing question regarding secondary fermentation
Post by: JJeffers09 on October 21, 2016, 12:06:14 AM
Look up CSA and you decide if transferring without the use of a closed system is real or can cause post-fermentation oxygen derived off flavors.  I have experienced them, I will say that it's not worth transferring unless your adding additional fermentables, I don't think it's worth it.  So as far as adding spices, I'm with Jon and don't advise it.

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Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 21, 2016, 12:55:43 AM
I don't think you will aerate the wort if you rack carefully. If your that worried don't do a secondary. Historically beer was brewed in open fermenters and coolships. The majority of home brewers don't do closed transfers. If you are you saying you can only make good beer in a closed system? I'll have to disagree
Title: Re: Timing question regarding secondary fermentation
Post by: Stevie on October 21, 2016, 02:59:43 AM
The issue with racking is all that surface area exposed to air. Purging helps, but closed transfers are better. The biggest issue is when folks don't fill the carboy to the neck. These leaves the beer exposed to plain air for however long.
Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 21, 2016, 03:24:35 AM
So basically your saying you can only make good beer by transferring with a closed system?
Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 21, 2016, 03:43:46 AM
http://howtobrew.com/book/section-1/fermentation/using-secondary-fermentors
Here is what John Palmer says about racking when still actively bubbling
Title: Re: Timing question regarding secondary fermentation
Post by: Stevie on October 21, 2016, 05:24:45 AM
So basically your saying you can only make good beer by transferring with a closed system?
I'm saying closed transfers are better and calling out some of the reasons why transfers can be an issue. I think Palmer has also changed his opinion in the 12 years since that version of how to brew came out.

Secondary "fermentations" are not necessary in most circumstances. Bulk aging or adding fruit are the only instances where I transfer to secondary vessel.
Title: Re: Timing question regarding secondary fermentation
Post by: JJeffers09 on October 21, 2016, 02:06:24 PM
I don't think you will aerate the wort if you rack carefully. If your that worried don't do a secondary. Historically beer was brewed in open fermenters and coolships. The majority of home brewers don't do closed transfers. If you are you saying you can only make good beer in a closed system? I'll have to disagree
You can aerate your wort transferring to a secindary, like already explained., however a few holes in your arguement I'd like to discuss. Open fermentation was only used in a primary fermentation then racked to a closed tank for aging and packaging.  The CO2 and the positive pressures created by the yeast during fermentation protects the yeast and the product. With a thick layer of co2 then yeast, then your beer.  When the krausen fell the beer was moved, preventing any extended exposure to the air.

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Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 21, 2016, 02:42:32 PM
By closed tank do you mean siphoned into an oxygen laden wooden barrel and sealed with a cork without purging. look I don't generally do secondaries but you don't have to be afraid of it ,plenty of brewers do it and have no problems. I want the OP to know you can make very good beer without doing closed transfers. Have you ever watched how beer is canned commercialy. On the home brew scale your wort is not going to be exposed long enough from a transfer. Hey does closed system have some benefit? Sure. Is it necessary? IMO no. Let's just agree to disagree.
Title: Re: Timing question regarding secondary fermentation
Post by: dilluh98 on October 21, 2016, 03:10:02 PM
I don't think you will aerate the wort if you rack carefully. If your that worried don't do a secondary. Historically beer was brewed in open fermenters and coolships. The majority of home brewers don't do closed transfers. If you are you saying you can only make good beer in a closed system? I'll have to disagree

Open fermentation does not mean active oxygenation of wort/beer - in fact, active fermentation is as low of oxygen content as a beer/wort mixture is ever going to get. That's why breweries can open ferment (and you can, too). Most breweries do transfers to conditioning tanks when fermentation is still happening because the threat of oxidation is low. Once fermentation stops, that's when you worry about oxygen exposure and hence people's call for closed transfer.
Title: Re: Timing question regarding secondary fermentation
Post by: JJeffers09 on October 21, 2016, 03:36:54 PM
By closed tank do you mean siphoned into an oxygen laden wooden barrel and sealed with a cork without purging. look I don't generally do secondaries but you don't have to be afraid of it ,plenty of brewers do it and have no problems. I want the OP to know you can make very good beer without doing closed transfers. Have you ever watched how beer is canned commercialy. On the home brew scale your wort is not going to be exposed long enough from a transfer. Hey does closed system have some benefit? Sure. Is it necessary? IMO no. Let's just agree to disagree.
Some beer styles it is appropriate to have those types of oxidized flavors.  A sherry-like or musty/cheesy aromas like in lambics it is preffered.  So stylistically it may be appropriate to have cellar aged flavors.  Others not so much.  Again head space in that barrel makes a difference too.  Sours are blended to get the right level of those flavors, however many have negative flavors due to oxygenation. 

It is subjective.  I am with you if your point is, "Its your homebrew, ultimately you get to decide"  a cinnamon/vanilla stout is not a bourbon barrel stout, a lambic, a sour, or any other.  It's a spiced holiday stout.  So I would be avoiding unnecessary steps and possible negatives is where possible off flavors could put an off character to the beer.

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Title: Re: Timing question regarding secondary fermentation
Post by: denny on October 21, 2016, 03:56:10 PM
Fermentation won't stall. Under aerated beer will stall. Ever add dry hops after 5 days? It starts fermenting again from the oxygen that gets in with the hops. The risk of oxidation comes after fermentation is complete. At least that's what I believe. But like I said if you're worried just toss it in the primary.

Have you checked to see if it's actually fermentation?  Often it's just CO2 coming out of solution due to the hops providing nucleation sites.  If the gravity actually drops, then it is continued fermentation.
Title: Re: Timing question regarding secondary fermentation
Post by: denny on October 21, 2016, 03:57:43 PM
http://howtobrew.com/book/section-1/fermentation/using-secondary-fermentors
Here is what John Palmer says about racking when still actively bubbling

John has changed his opinion since that was written.  https://www.homebrewersassociation.org/forum/index.php?topic=15108.msg191642#msg191642

An excerpt...."Therefore I, and Jamil and White Labs and Wyeast Labs, do not recommend racking to a secondary fermenter for ANY ale, except when conducting an actual second fermentation, such as adding fruit or souring. Racking to prevent autolysis is not necessary, and therefore the risk of oxidation is completely avoidable. Even lagers do not require racking to a second fermenter before lagering. With the right pitching rate, using fresh healthy yeast, and proper aeration of the wort prior to pitching, the fermentation of the beer will be complete within 3-8 days (bigger = longer). This time period includes the secondary or conditioning phase of fermentation when the yeast clean up acetaldehyde and diacetyl. The real purpose of lagering a beer is to use the colder temperatures to encourage the yeast to flocculate and promote the precipitation and sedimentation of microparticles and haze."
Title: Re: Timing question regarding secondary fermentation
Post by: dilluh98 on October 21, 2016, 03:57:58 PM
Fermentation won't stall. Under aerated beer will stall. Ever add dry hops after 5 days? It starts fermenting again from the oxygen that gets in with the hops. The risk of oxidation comes after fermentation is complete. At least that's what I believe. But like I said if you're worried just toss it in the primary.

Have you checked to see if it's actually fermentation?  Often it's just CO2 coming out of solution due to the hops providing nucleation sites.  If the gravity actually drops, then it is continued fermentation.

Yup, that's what I was thinking.
Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 21, 2016, 04:41:39 PM
Exactly. That is why I said to rack before fermentation is done.
Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 21, 2016, 05:04:35 PM
Well D I never secondary anymore. But I add my dry hops at krausen drop but it is probably still fermenting a bit. As far as weather the O2 in the hops or the nucliation is causing the increased activity I do not know but I feel better that the head space is being purged either way.
Title: Re: Timing question regarding secondary fermentation
Post by: denny on October 21, 2016, 05:12:55 PM
Well D I never secondary anymore. But I add my dry hops at krausen drop but it is probably still fermenting a bit. As far as weather the O2 in the hops or the nucliation is causing the increased activity I do not know but I feel better that the head space is being purged either way.

That's certainly one way you can do it.  I prefer to wait til fermentation is done, get the beer off the yeast, and then dry hop.  Both methods work, it's just a question of the result you want.
Title: Re: Timing question regarding secondary fermentation
Post by: JJeffers09 on October 22, 2016, 12:26:31 AM
Exactly. That is why I said to rack before fermentation is done.
Why do you suggest that at all? What benefit would your beers have to racking off of the yeast cake/trub prior to finishing?

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Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 22, 2016, 04:24:06 AM
If you read the original post it was about racking onto fermentable additions which is the only reason imo to rack to a secondary
Title: Re: Timing question regarding secondary fermentation
Post by: Stevie on October 22, 2016, 06:40:07 AM
If you read the original post it was about racking onto fermentable additions which is the only reason imo to rack to a secondary
The op doesn't mention fermentables.
Title: Re: Timing question regarding secondary fermentation
Post by: Brew Cat on October 22, 2016, 06:53:55 PM
If you read the original post it was about racking onto fermentable additions which is the only reason imo to rack to a secondary
The op doesn't mention fermentables.
True. He says ingredients so maybe he meant spices. If that's the case I wouldn't secondary.
Title: Re: Timing question regarding secondary fermentation
Post by: dunngood on October 25, 2016, 06:19:19 PM
One of my biggest concerns about racking off the primary yeast cake to soon is the yeast has not cleaned up the off flavors yet.
Title: Re: Timing question regarding secondary fermentation
Post by: denny on October 25, 2016, 06:28:42 PM
One of my biggest concerns about racking off the primary yeast cake to soon is the yeast has not cleaned up the off flavors yet.

Doesn't quite work like that....here's some info from John Palmer that will appear in an upcoming BYO article I'm writing....

Yeast have 3 phases in their life cycle: Adaptation, High Growth, and Stationary. (See Yeast by CW and Jamil) They do not have a maturation phase where they clean up byproducts. Adaptation phase is where they take in oxygen and build sterols and other lipids, assess the sugar composition and build enzymes, etc. Once those activities are done, they start the High Growth Phase, eating and reproducing. The number of cell divisions is limited by their lipid reserves they made during Adaptation. These reserves are shared with each daughter cell. When those lipid reserves are exhausted, the cell stops reproducing. In addition, when those reserves are exhausted, the cell is old and cannot eat or excrete waste efficiently across it’s cell membrane. A yeast cell typically can reproduce about 4 times during a typical fermentation, after that it is old and tired and tends to enter Stationary phase where it shuts down most of its metabolism and flocculates, waiting for the next batch of aerated wort. Stationary phase is essentially an inactivity phase, resting on the bottom.

Like I said, no conditioning phase as far as the yeast are concerned. Byproducts can be consumed at any point during the high growth phase, but they are a lower energy source than sugar, so guess what? Byproducts are not a biological priority. The brewer therefore needs to plan his pitching rate and fermentation conditions such that the yeast run out of fermentable wort sugar before their lipid reserves are exhausted and they go into stationary phase. Now you have a majority of vigorous yeast that have only undergone 2 reproductions (for example), the sugar is gone, and they are still hungry, so they turn to acetaldehyde and diacetyl as alternate energy sources and maturate the beer. You can help this by doing a diacetyl rest by raising the temperature a few degrees after the first half of fermentation, to keep the yeast active and eating. Where in the fermentation? after the first half, 2/3 to 3/4, when most of the attenuation has occured and raising the temperature is not going to cause rampant growth and the off-flavors associated with it.

Title: Re: Timing question regarding secondary fermentation
Post by: dunngood on October 25, 2016, 06:38:18 PM
Interesting I will have to check that out. Thanks.
Title: Re: Timing question regarding secondary fermentation
Post by: JJeffers09 on October 25, 2016, 07:07:58 PM
Denny isn't a D-Rest a step within the final phase of the yeasts life cycle? the Stationary phase? that I believe Chris White Ph.D put out an article discussing these phases. The Lag Phase, The Exponential Growth Phase, and the Stationary Phase.

            ...."Beer is matured in the stationary phase of growth, also known as the conditioning phase. Yeast reabsorb diacytyl that was produced during fermentation, and hydrogen sulfide escapes from the top of the fermentor as a gas."...

*edit - I only say anything at all because I think it does work that way, but not the way most people think.  There is a "conditioning" period where during the later stages of the growth phase and the beginning-middle of stationary phases beer is metabolizing "off flavors" such as diacetyl and acetaldehyde, like you mentioned.  However that continues past the growth phase of "active" fermentation.  Probably not as late as most people assume it is happening.  But to say that off flavors are not reduced in the conditioning phase is to say there is no such thing as "green beer" and I don't believe that to be true.
Title: Re: Timing question regarding secondary fermentation
Post by: dunngood on October 25, 2016, 09:18:15 PM
I was also referring to books by Greg Noonan when he states with a clean fermentation, it is usual for the beer to be held in the primary fermenter for two to three days after the kraeusen head has fallen. And the beer not be racked off its yeast sediment until diacetyl has been reabsorbed.
I get the idea that the primary yeast cake helps in some way with this process.
Title: Re: Timing question regarding secondary fermentation
Post by: brewinhard on October 25, 2016, 09:24:21 PM

I get the idea that the primary yeast cake helps in some way with this process.

Yes, it simply allows more yeast in contact with the beer to allow for more fermentation byproducts to be absorbed, consumed, and transformed.
Title: Re: Timing question regarding secondary fermentation
Post by: Phil_M on October 25, 2016, 11:14:27 PM
One of my biggest concerns about racking off the primary yeast cake to soon is the yeast has not cleaned up the off flavors yet.

Doesn't quite work like that....here's some info from John Palmer that will appear in an upcoming BYO article I'm writing....

Yeast have 3 phases in their life cycle: Adaptation, High Growth, and Stationary. (See Yeast by CW and Jamil) They do not have a maturation phase where they clean up byproducts. Adaptation phase is where they take in oxygen and build sterols and other lipids, assess the sugar composition and build enzymes, etc. Once those activities are done, they start the High Growth Phase, eating and reproducing. The number of cell divisions is limited by their lipid reserves they made during Adaptation. These reserves are shared with each daughter cell. When those lipid reserves are exhausted, the cell stops reproducing. In addition, when those reserves are exhausted, the cell is old and cannot eat or excrete waste efficiently across it’s cell membrane. A yeast cell typically can reproduce about 4 times during a typical fermentation, after that it is old and tired and tends to enter Stationary phase where it shuts down most of its metabolism and flocculates, waiting for the next batch of aerated wort. Stationary phase is essentially an inactivity phase, resting on the bottom.

Like I said, no conditioning phase as far as the yeast are concerned. Byproducts can be consumed at any point during the high growth phase, but they are a lower energy source than sugar, so guess what? Byproducts are not a biological priority. The brewer therefore needs to plan his pitching rate and fermentation conditions such that the yeast run out of fermentable wort sugar before their lipid reserves are exhausted and they go into stationary phase. Now you have a majority of vigorous yeast that have only undergone 2 reproductions (for example), the sugar is gone, and they are still hungry, so they turn to acetaldehyde and diacetyl as alternate energy sources and maturate the beer. You can help this by doing a diacetyl rest by raising the temperature a few degrees after the first half of fermentation, to keep the yeast active and eating. Where in the fermentation? after the first half, 2/3 to 3/4, when most of the attenuation has occured and raising the temperature is not going to cause rampant growth and the off-flavors associated with it.

Ok, this has me intrigued, and explains a good bit. With open fermentation with top droppings strains, some breweries skim the yeast off the top and keep re-oxygenating in order to try and keep the yeast in the growth phase.

It'd be interesting to try and see what sort of affect this has on home brewing...going to have to re-read the yeast book and try again...
Title: Re: Timing question regarding secondary fermentation
Post by: JJeffers09 on October 26, 2016, 02:13:33 AM
Top cropping yeast isn't "re-oxygenating" the wort.  It is obtaining a fresh culture of yeast for the next batch man not oxygenation.  Yeast gets all of its O2 during the Lag phase not the growth phase.  Or at least that's not what most Ph.Ds say on the matter...

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Title: Re: Timing question regarding secondary fermentation
Post by: Saccharomyces on October 26, 2016, 04:21:24 PM
The stage where the yeast cells are resting is known as "quiescence."  The stationary phase occurs when the yeast cells have reached maximum cell density or carbon has become limiting (sugar is carbon bound to water; hence, the term carbohydrate).  During the stationary phase, reproduction is for replacement only.

The risk of oxygenation is low until the yeast cells have been filtered from the beer.  Any yeast cells that are still in suspension during transfer will rapidly consume any O2 that is picked up.  The decision to rack should be made on what one wishes to accomplish.  When bottom cropping, the beer should be racked into a maturing vessel shortly after fermentation has subsided.  One does not want the yeast cells that are still in suspension to settle into the crop, as those cells usually have lost their ability to floc (aggregate), which is a common mutation. 

Separating the medium floculating cells from the early floculaters in the crop can be accomplished by swirling, allowing the heaviest fraction to settle, and cropping the topmost 250 to 350 milliliters of the liquid fraction.  Most of the cells in that part of the crop should be medium flocculaters that are still viable.

Title: Re: Timing question regarding secondary fermentation
Post by: ynotbrusum on October 26, 2016, 06:05:46 PM
The stage where the yeast cells are resting is known as "quiescence."  The stationary phase occurs when the yeast cells have reached maximum cell density or carbon has become limiting (sugar is carbon bound to water; hence, the term carbohydrate).  During the stationary phase, reproduction is for replacement only.

The risk of oxygenation is low until the yeast cells have been filtered from the beer.  Any yeast cells that are still in suspension during transfer will rapidly consume any O2 that is picked up.  The decision to rack should be made on what one wishes to accomplish.  When bottom cropping, the beer should be racked into a maturing vessel shortly after fermentation has subsided.  One does not want the yeast cells that are still in suspension to settle into the crop, as those cells usually have lost their ability to floc (aggregate), which is a common mutation. 

Separating the medium floculating cells from the early floculaters in the crop can be accomplished by swirling, allowing the heaviest fraction to settle, and cropping the topmost 250 to 350 milliliters of the liquid fraction.  Most of the cells in that part of the crop should be medium flocculaters that are still viable.

Great info, as always, Mark.  You indicate that the yeast in suspension will consume the O2 from the racking process.  My concern is whether it is best to rack a point or two Plato above FG to ensure this O2 consumption or to attempt keg priming to assure that yeast scavenge the O2.  Thinking stability of the finished beer here...also whether to use an auto siphon or avoid it for oxidation concerns.
Title: Re: Timing question regarding secondary fermentation
Post by: dilluh98 on October 26, 2016, 09:03:19 PM
Any yeast cells that are still in suspension during transfer will rapidly consume any O2 that is picked up.  The decision to rack should be made on what one wishes to accomplish. 

Mark, is aerobic oxidation of fuel necessary to scurb this oxygen? If not, what is the pathway for uptake of this oxygen ingress by the yeast?