Secondary fermentation and oxygen

[dyqik]

I think you missed my picture on page three of this discussion. As mentioned in the OP, this is about a closed CO2 transfer, from one glass carboy to another. There is no bucket. There is no oxygen coming in to the primary vessel. CO2 pressure is pushing the beer into the secondary. I appreciate your effort to explain this to me. I read the whole post.

I was just thinking about the CO2 blanket myth and carboys generally. This is why pressurized transfer is a nice thing to go for.

 

[bradleypariah]

I was just thinking about the CO2 blanket myth and carboys generally. This is why pressurized transfer is a nice thing to go for.

Agreed, but still I have a hard time calling it a "myth". There are so many videos that prove gas will sit in a container at room temperature for extended periods of time. I'm not a scientist, so I need to stop embarrassing myself by trying to explain why the gas sinks, be it temperature-related or otherwise, I just know that the more of a gas you push into an already-air-filled vessel, the more of the gas there will be, thus minimizing exposure to the air once you start pumping liquid into said gas-filled container. It's like some people are so convinced that gasses mix and dissipate so quickly, they wouldn't even admit that they were crying in a room filled with tear gas. They'd be too busy shouting at me, "*COUGH* The gas is *COUGH* MIXING!! Not *HACK* DISPLACING the oxy-*COUGH*WHEEZE*" LOL It's like, if gas mixes to impotency so fast, why you chokin' homey?

Whatever makes people sleep better at night. The point is that the gas is there. It doesn't just vanish because magic. If you pump CO2 into a carboy for several seconds, there's going to be a lot of CO2 in it, and it will remain there until some other force or atmospheric pressure acts on it. If nothing acts on it directly, it will most likely take upwards of a half of an hour to fully mix with the room's air. I used to think it would take longer, but MadKing's post about air and gas mixing over time proved me wrong. That said, 20 minutes, hell, five minutes is still plenty of time to rack a beer.

So, "myth"? No. "Misconception about why it works"? Yeah.

 

[TheMadKing]

Agreed, but still I have a hard time calling it a "myth". There are so many videos that prove gas will sit in a container at room temperature for extended periods of time. I'm not a scientist, so I need to stop embarrassing myself by trying to explain why the gas sinks, be it temperature-related or otherwise, I just know that the more of a gas you push into an already-air-filled vessel, the more of the gas there will be, thus minimizing exposure to the air once you start pumping liquid into said gas-filled container. It's like some people are so convinced that gasses mix and dissipate so quickly, they wouldn't even admit that they were crying in a room filled with tear gas. They'd be too busy shouting at me, "*COUGH* The gas is *COUGH* MIXING!! Not *HACK* DISPLACING the oxy-*COUGH*WHEEZE*" LOL It's like, if gas mixes to impotency so fast, why you chokin' homey?



Whatever makes people sleep better at night. The point is that the gas is there. It doesn't just vanish because magic. If you pump CO2 into a carboy for several seconds, there's going to be a lot of CO2 in it, and it will remain there until some other force or atmospheric pressure acts on it. If nothing acts on it directly, it will most likely take upwards of a half of an hour to fully mix with the room's air. I used to think it would take longer, but MadKing's post about air and gas mixing over time proved me wrong. That said, 20 minutes, hell, five minutes is still plenty of time to rack a beer.



So, "myth"? No. "Misconception about why it works"? Yeah.

I don't disagree with you that in practice, this works fine. The only hole in this is that you're allowing for "some mixing" to occur. So I ask What threshold is acceptable to you then? Some people find 1ppm oxygen to be too much, so what happens if 10% of the gas in your container is air? How much O2 is dissolved into your beer then?

How can you really control how much oxygen you're dealing with unless you're either measuring it, or taking extreme steps to eliminate it entirely? And if you're not trying to control your oxygen levels but just trying to "minimize" then how much is too much? It's all arbitrary unless you apply repeatable methods that are scientifically sound.

On the other hand, as I said earlier, I think oxygen is not a detrimental as many people believe and basic precautions applied to the right parts of the brewing process will prevent off flavors. Just don't leave your beer exposed to air for any length of time, and purge the headspace in any vessel down to ~0.1ppm oxygen (~10 purges at 30psi in a keg). At the end of the day, do what works for you and what makes beer you can be happy with.

 

[bradleypariah]

I don't disagree with you that in practice, this works fine. The only hole in this is that you're allowing for "some mixing" to occur. [...] How can you really control how much oxygen you're dealing with unless you're either measuring it, or taking extreme steps to eliminate it entirely? [...] as I said earlier, I think oxygen is not a detrimental as many people believe and basic precautions applied to the right parts of the brewing process will prevent off flavors.

We're pretty much on the same page. I am not a purist. I didn't mean to come off as one. I'm not super worried about oxygen either. I just want my yeast so I can brew again. I'm merely sharing a technique that was shared with me to attempt to minimize potential harm to the beer. I think racking to secondary is unnecessary unless you're trying to get your yeast or you're wanting to add fruit. Sometimes simply trying to minimize problems can make all the difference, so I bother to try.

 

[oujens]

I liked the idea of filling a keg completely with sanitizer and purging it completely with co2. This would avoid the diffusion mentioned above. I thought of doing the same thing, transferring to a purged vessel when fermentation was almost complete but was counselled not to transfer when active fermentation was taking place. The reason for this was that perhaps it could stall and it was deemed to be 'bad practice'. I have a spunding valve but have never used it. In your opinion is it ok to wait till there is a few OG points and to transfer to another Keg and spund out the remaining fermentation?

Spunding has worked well for me. I don't believe transferring towards the end of fermentation is detrimental to the final product. In fact, I have a local Brewery who specifically states they capture co2 from fermentation to carb their beer. What I'm not sure of is whether they transfer prior to spunding, but I thought they finish in a conditioning tank prior to lagering. Enough people have reported success with spunding (including transferring with few gravity points remaining) that I would not hesitate to use it. Note there was mention of this process before the "paper" ever hit the message boards. It's nothing new. Of course, this is just one way to handle cold side practices. YMMV, but I think it's a good practice. Only difficult part is timing, but if you miss the window you can let it finish and then use the priming sugar method to scrub o2 during transfer.

 

[Syke]

If anyone knows how to get a sufficient yeast sample from there without moving the beer, I'd love to hear it.

Harvest some yeast before pitching and make a starter.

 

[kh54s10]

I don't do secondaries. I bank yeast BEFORE pitching by making 4 vials from my slightly oversized starter. 5 ml Glycerin, 5 ml yeast and 10 ml water, then frozen. I will also sometimes use part of a yeast cake for a new batch. I do not use a secondary to get the yeast. I just package the beer then either use the yeast cake right away, or put it in a mason jar and save in the refrigerator. I use 6 gallon Better Bottles. Personally I cannot justify the cost of a conical fermenter. My 7 better bottles probably cost only a little over $100 since I bought some of them on buy one get one sales.

 

[jan_b19]

transferring early (just after high krausen does indeed reduce oxidation chance. the beer will keep fermenting and push the oxygen out of the vessel. If you want to be sure you could add a little amount of campden like they do for wine. small amounts (1g or less/10 liters) will not affect the taste of the beer at all.
This discussion has been going on for ages. Some people like to rack to a secondary others don't. I only rack if the beer has to ferment for longer than a month. For example, brewed a saison, I let my saisons ferment for at least 6 weeks. I chose to rack it to a secondary after two weeks exactly for the reasons you described. I like to rack it when they yeast is still very active so there is a smaller chance for oxidation.

 

[MSK_Chess]

It appears to me that one should not be dogmatic and there are certainly many instances when racking is not only essential but highly beneficial other occasions when its not. I really thank those who have expressed their opinions and provided sound reason and empirical evidence when it is necessary to rack and when it is not. We are home-brewers, a kind of artist/scientist hybrid that wants to understand the processes that we are helping nature to foment in order to improve our process to make the best we can with the ingredients we have at our disposal. Understanding is surely the thing to be aimed for - a hearty sláinte! to all

 

[MSK_Chess]

I don't do secondaries. I bank yeast BEFORE pitching by making 4 vials from my slightly oversized starter. 5 ml Glycerin, 5 ml yeast and 10 ml water, then frozen. I will also sometimes use part of a yeast cake for a new batch. I do not use a secondary to get the yeast. I just package the beer then either use the yeast cake right away, or put it in a mason jar and save in the refrigerator. I use 6 gallon Better Bottles. Personally I cannot justify the cost of a conical fermenter. My 7 better bottles probably cost only a little over $100 since I bought some of them on buy one get one sales.

I'd love to try freezing yeast. You could build up a bank of many different varieties and have them at your disposal at any time.

 

[dyqik]

Agreed, but still I have a hard time calling it a "myth". There are so many videos that prove gas will sit in a container at room temperature for extended periods of time.

As I said and showed above, those videos do not demonstrate anything that is particularly relevant to the low-level oxidation of beer. They show that a concentration gradient takes significant time to dissipate by diffusion, and that _much_ of a gas will stay in place in layers for some time. They do not show that gas sits in well-defined layers that prevents one gas moving through another. We don't care what happens to the bulk of the gas. What we care about is how much trace oxygen gets through the layer. The reason I call it a myth is that the layer of CO2 doesn't protect the beer for very long, as oxygen can diffuse through it, and in any case, that layer is very easily disturbed by opening lids, drafts and generally moving equipment around.

This is something I have to deal with in my work - we use open liquid nitrogen containers as a reference temperature load. There's a clearly visible boundary layer between the cold (~200-100 Kelvin) dense nitrogen gas boiled off of the liquid at the top of the container that stays in place for several hours. But over half an hour or so, the boiling point of the liquid nitrogen rises by several degrees as oxygen from the air diffuses through this layer of cold nitrogen gas and dissolves in the liquid. The boiling point of the liquid is a reasonably sensitive measure of the oxygen content of the mixture.

 

[dyqik]

And yes, many beers don't need extreme steps to prevent oxidation to achieve good examples of the style, and are just fine with minimal precautions. English and other cask or aged styles in particular are fine with just basic prevention of splashing, and natural carbonation in the pressure barrel/cask/keg/bottle.

Some styles however, have only really come about as high quality beers because oxidation can be very well controlled on the micro-brewery scale. NEIPA in particular (I suspect this is because bio-transformed hop compounds are very prone to oxidation), and I don't think it would exist as a style if the breweries that developed it had similar oxidation levels to standard homebrew procedures.

 

[kh54s10]

I'd love to try freezing yeast. You could build up a bank of many different varieties and have them at your disposal at any time.

Here is one of the threads that I looked at before I started: https://www.homebrewtalk.com/showthread.php?t=35891

I don't heat sterilize. I just soak all my equipment in Starsan.

If you want to try this, I suggest that you search for threads and videos. Watch and read them all, and figure out a procedure that will work for you. Whenever I start something new I look at a lot and start with what all the videos/threads have in common. I mostly ignore anything that only one or two give as a needed step.

 

[TrustyOlJohnson]

I dont secondary beers unless primary fermentation is complete and Im racking onto fruit or oak chips.. I did a few times in the beginning, but see no value in it.
Risk of infection..
Exposure to oxygen..
Autolysis doesn't happen in 5 gallon batches..
It is extra risk and work with no reward.
I ferment my ales at 62/65/68, 5 or 7 days each depending on whether it is a low or high gravity beer, for a total of 15 or 21 days, then rack to bottling or keg.

 

[ZmannR2]

My beers taste INCREDIBLE...better than anything I get in stores....never once have I racked to secondary....I've always cold crashed on the yeast cake and never once have had off flavors....my beers are crystal clear once in the keg a week or two...just see below, those letters are on the back side of the glass:

 

[MSK_Chess]

Here is one of the threads that I looked at before I started: https://www.homebrewtalk.com/showthread.php?t=35891

I don't heat sterilize. I just soak all my equipment in Starsan.

If you want to try this, I suggest that you search for threads and videos. Watch and read them all, and figure out a procedure that will work for you. Whenever I start something new I look at a lot and start with what all the videos/threads have in common. I mostly ignore anything that only one or two give as a needed step.

I like this guy. He inspires confidence.
[ame]https://www.youtube.com/watch?v=EMFWHm61NEU[/ame]

 

[MSK_Chess]

My beers taste INCREDIBLE...better than anything I get in stores....never once have I racked to secondary....I've always cold crashed on the yeast cake and never once have had off flavors....my beers are crystal clear once in the keg a week or two...just see below, those letters are on the back side of the glass:

not bad, head retention might be better though