Racking - Headspace?

[Keith the Beer Guy]

Hi Brian,

welcome to the site.

My only concern is that I'm not sure I should bottle if I still have some fermentation activity. It seems like I should get a complete cessation or is this incorrect? If I have a really good seal, then I would be getting a much better indication of activity than you would with an airlock.

Cheers, Brian

[post="107965"][/post]​

The quick answer is that an air-lock can bubble for a long time after you rack.

My advice is to trust your hydrometer - not your airlock!

Is "zero" fementation/yeast activity before bottling a misunderstanding? Do the yeast really stop or just slow way down?

Malt has a whole bunch of sugars in it. Some of these sugars are easy to ferment, some are hard to ferment and some never get chewed up by the yeast. In the rush of primary fermentation the easy to chew sugars are chomped up by the yeasts. In the secondary the yeast settles down and does a couple of things, one of which is chewing up some of the harder to ferment sugars. If you have a big black beer with plenty of these hard to chew sugars the yeast will keep on eating them for months perhaps years after you bottle your beer. (Making for some very over-carbonated stouts)

I cant help myself, but I gotta add - I would skip the addition of the sugar when you rack. I'm a big believer in not doing stuff that doesn't need to be done. Instead, just rack your beer a little earlier. When the rush of the primary ferment starts to slow down, your krausen starts to fall back into the beer and the airlock bubbles a little bit less. This is a good time to rack.

Cheers,

Keith

 

[PostModern]

... just rack your beer a little earlier...

[post="107972"][/post]​

Gotta say Keith, that this point is frought with debate. Racking too soon can cause some probs. Firstly, underattenuation - racking beer off the yeast cake too soon can leave too few yeast in secondary to finish the job. Beer should almost always be racked after a complete primary fermentation. Second prob, as you correctly point out, once the rush of primary is over, yeast work on the harder to complete sugars. They also re-absorb some of their own by-products. Removing the brew from the yeast cake leaves not enough cells to finish this clean-up... My rule of thumb is to rack 3 days after a steady OG is recorded. (talking of ales mostly, lagers tend to spend plenty enough time in primary to clean up as they go, afaik).

*/me dons flame suit*

 

[Simon W]

They also re-absorb some of their own by-products.

A great example of this occured to me recently.
I was forced to bottle an AG IPA prematurely to have a few drinks ready for the Australia Day weekend. The drinks I had that weekend reeked of diacetyl, still tasted okay tho.
The two I had lastnight however were perfect, not even a hint of diacetyl.
Yeast was S-04, which I find tends to take forever to floc, so there was plenty in the stubby to do the job. Still quite cloudy actually.
If I had done the same but used finings or gelatin to clear it, they'd probably still reek and be quite sweet.

Edit: Speeling

 

[tangent]

i'd use alternatives to the sugar idea, only because I'm noticing VERY cidery flavours from bottles even primed with a dash of sugar. I don't know if I'm noticing it more than I used to or what.
You could use a little squirt from the C02 cylinder or one trick I've seen from winemakers is to drop a piece of dry-ice in.
I just rack and say "she'll be right" and she always has been

 

[Keith the Beer Guy]

Hey PoMo,

*/me dons flame suit*

[post="107992"][/post]​

No need to practise safe discourse.

I'm more than happy to be wrong about something... or wrong about many things for that matter... providing my wrongness doesn't diminish my appreciation for the cultural influence that the Simpsons has on the world.

One of the things I like about this site is vigorous debate. It gives me the chance to learn new stuff or clarify a concept or an idea that has been floating around in the back of my head.

... just rack your beer a little earlier...

[post="107972"][/post]​

Gotta say Keith, that this point is frought with debate. Racking too soon can cause some probs. Firstly, underattenuation - racking beer off the yeast cake too soon can leave too few yeast in secondary to finish the job. Beer should almost always be racked after a complete primary fermentation. Second prob, as you correctly point out, once the rush of primary is over, yeast work on the harder to complete sugars. They also re-absorb some of their own by-products. Removing the brew from the yeast cake leaves not enough cells to finish this clean-up... My rule of thumb is to rack 3 days after a steady OG is recorded. (talking of ales mostly, lagers tend to spend plenty enough time in primary to clean up as they go, afaik).

*/me dons flame suit*

[post="107992"][/post]​

I guess, for me, it comes down to this.

My understanding is that at the bottom of a fermenter you have a bunch of stuff: hop residue, maybe some left over proteins from hot/cold breaks, yeast that didn't make the grade, and yeast that has gone dormant.

Hard working healthy yeast is floating around in the beer.

I rack when the primary slows down and I usually use, as a visual clue, the collapsing krausen (or the action in the airlock slowing down which happens at the same time).

What I think I'm doing when this happens is that I am getting rid of the crap, and moving healthy yeast to my secondary to get on with the whole conditioning part of the process.

Removing the brew from the yeast cake leaves not enough cells to finish this clean-up...

[post="107992"][/post]​

The questions I have are:

Isn't the yeast doing the work floating around in the beer?
Isn't the yeastcake formed from yeast that has gone dormant after doing their share of fermentation?

Thanks for the post PoMo,

Keith

 

[Ross]

Keith,

If you want to remove the hop debris etc, try racking after 24hrs - Several UK breweries do this "double dropping" & it supposedly improves the beer - Quoting Marston's Brewery spiel "It brings out the full flavour of the malt, allowing only the most vigorous yeast to survive, resulting in a cleaner fermentation process & a fresher, brighter beer"

I guess the added oxygen from the transfer at this early stage doesn't go amiss either, in getting a healthy ferment going...

cheers Ross...

 

[tangent]

have you been doing this Ross?
24hours after inoculation or after a krausen forms?

 

[Ross]

have you been doing this Ross?
24hours after inoculation or after a krausen forms?

[post="108057"][/post]​

Tangent,

No, haven't tried myself, not sure if the benefits warrant the extra work in my case... but may give a try one day...

24 hrs from ferment start, I believe...

cheers Ross

 

[Gulf Brewery]

have you been doing this Ross?
24hours after inoculation or after a krausen forms?

[post="108057"][/post]​

Tangent

I would not be risking adding extra oxygen more than 12 to 14 hours after the yeast has been pitched - I know some do re-oxygenate at this point for big beers (OG > 1.080) , but unless you really know what you are doing, it may make matters worse rather than better. At this point the yeast is switching the anaerobic functions and any excess oxygen will stay in the beer and cause hassles later especially if the beer is going to be stored for a long time. 24 hours after krausen is defiinitely too late to even think of adding oxygen.

Cheers
Pedro

 

[Ross]

have you been doing this Ross?
24hours after inoculation or after a krausen forms?

[post="108057"][/post]​

Tangent

I would not be risking adding extra oxygen more than 12 to 14 hours after the yeast has been pitched - I know some do re-oxygenate at this point for big beers (OG > 1.080) , but unless you really know what you are doing, it may make matters worse rather than better. At this point the yeast is switching the anaerobic functions and any excess oxygen will stay in the beer and cause hassles later especially if the beer is going to be stored for a long time. 24 hours after krausen is defiinitely too late to even think of adding oxygen.

Cheers
Pedro

[post="108065"][/post]​

Pedro, I guess they transfer without splashing then at this stage ...

cheers Ross

 

[tangent]

thanks

 

[Weizguy]

<abbrev> The questions I have are:

Isn't the yeast doing the work floating around in the beer?
Isn't the yeastcake formed from yeast that has gone dormant after doing their share of fermentation?

Thanks for the post PoMo,

Keith </abbrev>

[post="108049"][/post]​

Keith,

Some of your assumptions are correct, but not complete.

Yep, the yeast still floating in the beer are working (not dormant), but are likely to be slow flocculators, and maybe slow workers, too. Maybe the hard workers have had enough beer and gone to bed?

Re the yeast cake: it's full of sleeping yeast, dead yeast and other bits of scrap/ trub. However, you will find that this is the yeast that you should propagate, according to the yeast "experts" such as Chris White.

Maybe with the "good" yeast, it's a case of "the candle that burns twice as bright, burns half as long".

Have I answered your questions, but given you more?

Seth

 

[Keith the Beer Guy]

Hey Seth,

thanks for the reply.

Yep, the yeast still floating in the beer are working (not dormant), but are likely to be slow flocculators, and maybe slow workers, too. Maybe the hard workers have had enough beer and gone to bed?

[post="108083"][/post]​

It had not occurred to me that some of my hard working yeast may have gone dormant and settled to the bottom before some their slow to flocculate mates got around to it. Thankyou kindly for introducing a new idea into my poor overworked brain.

Re the yeast cake: it's full of sleeping yeast, dead yeast and other bits of scrap/ trub. However, you will find that this is the yeast that you should propagate, according to the yeast "experts" such as Chris White.

Maybe with the "good" yeast, it's a case of "the candle that burns twice as bright, burns half as long".

Have I answered your questions, but given you more?

[post="108083"][/post]​

You have indeed (or will indeed) make me think about my yeast propagating methods. No more grabbing the yeast from the rack, I will stick to the primary.

However, in the context of the right time to rack your beer - doesn't this all add weight to racking your beer just as the primary winds down? You have more of your hard working yeasts doing their thing, the longer you leave it to rack, the more of your hard workers will be taking a snooze and not be around to condition your beer.

Cheers,

Keith

 

[Borret]

Can't say I agree with the assumption that the yeast cake is all dormant.... Have we never had a look at the activity in a starter that is building cells and litterally creating it's own havoc.. Most of that gas is being created at the base where all that nice active yeast is and nice big globs are shooting to the surface as they create a pocket of gas, then either falling down to the bottom once the gas escapes or adding to the top cropping bublegum head.
Yes I agree that yeast in suspension is doing a great deal of work but I hardly agree that the yeast at the bottom is asleep. It may be there with break material and hop trub but it's still chewing away. Even if finished it's primary course of the feast it is onto desert with the harder to stomach stuff. It's just like a buffet when any one can eat any course they please all at the same time.

I personally am a rack at the end of primary activity kind of brewer to a glass secondary where you can observe beer clearing before your very eyes. As there is always enough yeast to work in the bottle at the end of secondary, I believe there is always enough at the end of primary to do the slow work in secondary. Some of the secondary is already happening in primary anyway.

I may be wrong but they be my opinions.

Brent

 

[Keith the Beer Guy]

Can't say I agree with the assumption that the yeast cake is all dormant.... Have we never had a look at the activity in a starter that is building cells and litterally creating it's own havoc.. Most of that gas is being created at the base where all that nice active yeast is and nice big globs are shooting to the surface as they create a pocket of gas, then either falling down to the bottom once the gas escapes or adding to the top cropping bublegum head.
Yes I agree that yeast in suspension is doing a great deal of work but I hardly agree that the yeast at the bottom is asleep. It may be there with break material and hop trub but it's still chewing away. Even if finished it's primary course of the feast it is onto desert with the harder to stomach stuff. It's just like a buffet when any one can eat any course they please all at the same time.

I personally am a rack at the end of primary activity kind of brewer to a glass secondary where you can observe beer clearing before your very eyes. As there is always enough yeast to work in the bottle at the end of secondary, I believe there is always enough at the end of primary to do the slow work in secondary. Some of the secondary is already happening in primary anyway.

I may be wrong but they be my opinions.

Brent

[post="108121"][/post]​

Thanks for the thoughts Brent,

My own thinking was that CO2 is simply nucleating at the bottom (where there is more stuff for it to happen) and thats why the bubbles were forming there. I dont know though, that was just the thought travelling around my head (I was thinking about ales with all the yeast thing happening at the top - you still get the churning ferment).

We're racking at the same time and I too am a big fan of glass. There is something magical about seeing your brew do its thing.

Cheers,

Keith

 

[BruceL]

Here is a link that looks at plastic bottles, O2 and CO2 permeability.

http://www.azom.com/details.asp?ArticleID=351

It shows that PET Bottles lose 10% of their carbonation in the first 40 days.

The article states that 1ppm O2 is detectable in light beers by trained tasters. Over a period of six months, a conventional PET container allows the beer to exceed this value by a factor of 30.

Lucky any bottled living yeast acts as an oxygen scavenger. However if you bottle filtered artificially carbonated beer (like many brew on site places), and use PET bottles you will need to be a fast drinker.

Plastic fermenters are obviously a lot thicker than PET bottles, so I would probably expect much lower permeability of both.

Bruce

 

[Goo]

Hey there - first up post here

Next payday I'm looking to buy another fermenter or a glass carboy and giving secondary fermenting a whirl

Reading this has pretty much talked me out of getting a glass carboy, I think I'll go with the plastic.

Just wondering the best method of racking the beer over now.. do I hook up my tube and do the 'coil round the bottom' thing like you might do for a priming bucket? do i just not sit the fermenter lid on properly and run the hose down through there? Am I going to need a hole in the lid instead to push the tube through? DO I pull the tube out when done and bung the hole?

Just wondering the best procedure for a safe racking really, assuming I'll be doing plastic fermenter to plastic fermenter

Thanks!