add a co2 gas layer during oxidation-sensitive operations?

[Horseflesh]

We'll be transferring a brew from a bucket to a carboy soon. Since you are not supposed to splash and oxygenate the beer, I thought about filling the carboy up with co2 before the transfer, displacing all the air, as extra insurance.

This could also be done when bottling, to prevent oxygen in the headspace--or do the yeast use oxygen metabolism during bottle conditioning?

Seems like this must be an old idea, and perhaps a bad idea or needlessly complicated since I've not seen it mentioned.

 

[bobbrewedit]

We'll be transferring a brew from a bucket to a carboy soon. Since you are not supposed to splash and oxygenate the beer, I thought about filling the carboy up with co2 before the transfer, displacing all the air, as extra insurance.

This could also be done when bottling, to prevent oxygen in the headspace--or do the yeast use oxygen metabolism during bottle conditioning?

Seems like this must be an old idea, and perhaps a bad idea or needlessly complicated since I've not seen it mentioned.

I've done this when transferring to a secondary carbon when I'm going to age the beer for an extensive period of time. I think most people skip it since co2 is not free, it's an extra step, and frankly, your beer will turn out fine without doing it.

 

[krispy3d]

I think most are just careful during the process. But insurance can be nice, depending on how anxious one is about messing something up. I also wonder about the bit of oxygen in the headspace of a bottle. Hopefully someone can answer that one for us.

 

[bobbrewedit]

I think most are just careful during the process. But insurance can be nice, depending on how anxious one is about messing something up. I also wonder about the bit of oxygen in the headspace of a bottle. Hopefully someone can answer that one for us.

The best way around this is to keg your beer, then use a bottle filler. My understanding is they purge each bottle with co2 just before they fill it.

 

[BrewKnurd]

commercial breweries typically purge their bottles with CO2 prior to bottling. At least some (maybe many) have a multistep purge where the purge, vacuum out the contents, purge again, and then fill. They do this for stability, because oxygen = bad. Will the yeast take up some of the O2, certainly. Will they take it all up? maybe not.

If you have the ability to CO2 purge, its not going to hurt and could help. I think they best way to see if its worth it for you would be to try a few bottles with and a few bottles without and see if you can tell a difference down the road. If you're going to drink or give away all your bottles within a couple weeks, you probably won't be able to tell a difference either way. If you're going to keep them for months, my suspicion is that you would be able to tell the difference after they've aged.

I know vinnie from russian river recommends, particularly for hoppy beers, that homebrewers purge their bottles with CO2 prior to bottling, because O2 can have a particularly significant impact on hop aroma and flavor compounds.