Oxidation and Racking

[MyCarHasAbs]

Never racked to secondary. I'm waiting three weeks on an Imperial Stout and considering racking for once. Before I commit to this decision I want to get on the same page as to what exactly causes oxidation when racking.

Is it:
A) having the top off for an extended period of time
B) the pump action used by the wine thief to suck up and get the flow of wort moving into the secondary vessel? I know I often have to pump a little hard to get a steady flow going when I got to bottle. I've never had an issue with it but wondering if this is the most common culprit for collecting unwanted nasties.

 

[Bowtiebrewery]

Oxidation typically occurs from prolonged contact of the wort or beer to air or from turbulence created from the siphoning process. So how do you combat this... Do you Keg?

When I Secondary, I purge my keg or secondary fermenter with a bunch of CO2, so there is almost no chance for oxidation. If you don't keg, I would just make sure that when you rack the tube that is sanitized and is going to your secondary fermenter; Make sure it is going all the way to the bottom of that fermenter. And try to make sure your secondary has little to no head space.

Similar to Wine the smaller the headspace, the less CO2 will have to come out of solution to take up and fill that headspace, and create less opportunity for air to beer contact.

 

[bobeer]

I would think that splashing the beer while racking it would be the #1 culprit of oxidation. I bottled beer for a long time before I started kegging and getting a tube long enough to go from the racking cane to the bottom of your bucket was pretty key in preventing splashing.

As long as you're careful and gentle with the beer it will be fine.

 

[drainbamage]

Also make sure you have a good siphon going. If there are bubbles in the line, there is air in the line. Give the auto-siphon a good pump to keep a steady stream. I also like to make sure the hose coils around the bottom of the container so the beer isn't spraying straight down against the bottom.

 

[MyCarHasAbs]

I don't have any sort of Kegging or C02 system. However I do have a tube that is PLENTY long enough. I wouldn't say there's ever any splashing involved, just some bubbling similar to if a child is playing with their straw drinking chocolate milk. I've never noticed an issue from the forced air bubbles though.
Since this beer missed the mark on the OG (was supposed to be 1.08 and I hit 1.07) I'm going to wait three weeks before taking a measure. If I like what I see I'll go ahead and just add my secondary elements to it while in primary and let it sit for another week before cold crashing. Trying to get this bad boy drinkable by Xmas. I'll save some bottles for a few months after but my impatience will get the better of me for the sake of 'the season' haha.
If it's showing that it's still taking it's time then I'll venture into the wild side. Also, it's currently in a 6gal carboy, I have a 5 gal to transfer to if need be for minimal headspace.

 

[slsBrewing]

Prolonged being the operative word here. You don't want a Large volume of oxygen (air) to be in contact with the beer for a Long period of time (days). You want to transfer your beer smoothly without a lot of turbulence/splashing.

With all that being said, you can have some splashing and some long term exposure without oxidation issues. And then… you can have oxidation issues that are cleaned up by the yeast.

Here is the story of my Saison: I split a 10gal batch with a friend, then split mine into two 3.5 gal better bottles and pitched different yeasts. I used aluminum foil instead of an airlock or blow-off tube (this minimizes back-pressure, increases oxygen exposure and increases ester production – but that’s another thread). I let them ferment for 2 weeks at 80-84*F before bottling. Primary fermentation was complete before week 1. I should have replaced the alum foil with an air-lock before the end of fermentation to prevent prolonged oxygen exposure(after fermentation), but I didn’t. I noticed that my final gravity samples were much darker (due to oxidation) than my friend’s. Eh, I bottled anyway. After a few weeks of bottle conditioning I was surprised to find that both of my saisons’ colors had returned to their lighter color and displayed no oxidation flavors. I attribute this to the yeast consuming the oxygen during bottle conditioning. I presume the same thing will happen during secondary; and to a much lesser extent in the keg. But don’t go getting haphazard with your quality control.

 

[slsBrewing]

If there are bubbles in the line, there is air in the line.

I kept noticing this on some of my beers and it really upset me, so I switched to a racking cane. Very happy with that decision. But sometimes it still happens, esp on a slow moving rack. In this case, I think it is CO2 coming out of solution during the racking process.

 

[MyCarHasAbs]

Prolonged being the operative word here. You don't want a Large volume of oxygen (air) to be in contact with the beer for a Long period of time (days). You want to transfer your beer smoothly without a lot of turbulence/splashing.

With all that being said, you can have some splashing and some long term exposure without oxidation issues. And then… you can have oxidation issues that are cleaned up by the yeast.

Here is the story of my Saison: I split a 10gal batch with a friend, then split mine into two 3.5 gal better bottles and pitched different yeasts. I used aluminum foil instead of an airlock or blow-off tube (this minimizes back-pressure, increases oxygen exposure and increases ester production – but that’s another thread). I let them ferment for 2 weeks at 80-84*F before bottling. Primary fermentation was complete before week 1. I should have replaced the alum foil with an air-lock before the end of fermentation to prevent prolonged oxygen exposure(after fermentation), but I didn’t. I noticed that my final gravity samples were much darker (due to oxidation) than my friend’s. Eh, I bottled anyway. After a few weeks of bottle conditioning I was surprised to find that both of my saisons’ colors had returned to their lighter color and displayed no oxidation flavors. I attribute this to the yeast consuming the oxygen during bottle conditioning. I presume the same thing will happen during secondary; and to a much lesser extent in the keg. But don’t go getting haphazard with your quality control.

So I'll take it a little bubbles here and there aren't a big deal.
Forgot to mention, it's going to be an Imperial Mint Chocolate Stout with Bourbon extract. I have both cocoa nibs and peppermints sitting in their own containers of vodka. Probably going to add some more cocoa powder after the 3 week marker.