Preventing Oxidation in Secondary During Lagering

[VarangianGarde]

Hi Folks!

Once the primary fermentation is complete when lagering, would it be wise to add a small amount of fermentable sugar to the secondary to reactivate the yeast and provide a small CO2 buffer in a glass carboy? Unfortunately my current setup is kegless/pressureless, so I'm trying to preserve the wort from oxidation during secondary while using nothing more than a 5 and 6.5 gallon glass carboy fermenter.

Has anyone tried this? If so, what fermentable did you use and at what weight per gallon? How did the beer turn out?

I'll be transferring to secondary this Sunday, so any input would be appreciated!

 

[MaxStout]

The racking from primary to secondary is what's going to add most of the O2, unless you can do a closed transfer. That refermentation to produce CO2 in secondary will be too late.

Why do you need to rack to secondary, anyway? You can keep the beer in primary for several months without fear of autolysis.

 

[VarangianGarde]

Thanks Max,

As I understand, secondary is better in the lagering process to allow the wort to age while removing the trub (which I've read can unbalance and roughen up a lager's flavor profile). I know that just by transferring, some oxidation is inevitable, but I figured that might still be acceptable if further oxidation was prevented by a small refermentation. Am I off base here? I dunno.

Also, is there a way to do a closed transfer with just a racking cane and carboys?

 

[MaxStout]

You can fill the secondary with Starsan, then push it out with CO2. Then rack the beer into it.

Do you have a CO2 tank & regulator? Use a carboy cap and racking cane. Push out the Starsan with about 2 psi. I've done it a few times, works great. Just make sure you don't apply too much CO2 pressure, as carboys aren't designed for that.

 

[VarangianGarde]

Unfortunately I don't. That's on the list for future acquisitions, but as of now I've just got my carboys with bung caps. Could I just do the diacetyl rest and then proceed to low temp lagering from primary, and if so, how would that affect the flavor?

 

[Beholder]

Unfortunately I don't. That's on the list for future acquisitions, but as of now I've just got my carboys with bung caps. Could I just do the diacetyl rest and then proceed to low temp lagering from primary, and if so, how would that affect the flavor?

I think it is a function of time. For short lagering (~weeks) secondary is most definitely debatable as to flavor effects of the the trub. For longer duration (~6 months), it would be advisable.

would it be possible to do a side-by-side with half the batch moved off into secondary and the other half staying on trub to answer the question for yourself?

To purge your secondary carboy, run your blow off into a sanitized secondary and run a tube from that into a water container. Depending on the carboy, you can get caps or bungs with two holes or connection points for the tubing.

 

[cmac62]

You could also use a little ascorbic acid or Kmeta to scavenge the O2 that is picked up during the transfer. Not sure on the amounts, but I hear it is effective.

 

[MaxStout]

IIRC, the LODO people suggest about 10ppm ascorbic or meta. Enough to scavenge some O2, but not enough to stunt the yeast.

 

[Beermeister32]

I don’t use a secondary. I believe most brewers are going primary straight into aging/lagering/serving keg. I quit using secondaries years ago, they are for the most part unnecessary.

If you want to add a tablespoon of corn sugar to the keg to scavenge O2, you can do so, or add 3/4 cup to fully carbonate the keg. You can add a teaspoon of ascorbic acid at this point as well if you prefer. I usually add gelatin later in the lagering process when the keg is 34F it works best cold. Make sure to purge your headspace well.

I usually age out most lagers 90 days in the keg. For heavier beers like an Oktoberfest, I lager for 180 days, sampling along the way. Build up your pipeline and the wait is a non-issue. Last year I had one great after just 2 months!

 

[GoeHaarden]

Honestly, I treat them pretty much like an ale. Two-ish weeks for fermentation -> cold crash w/wo gelatin for about a week. Then keg -> force carb at serving pressure and temp for 2 weeks -> and tap.

You can do the same in bottles as well...

 

[Beermeister32]

I don’t cold crash in a carboy, it can cause suck back of air unless you have preventative measures.

I prefer to do a D-rest near the end of fermentation, then transfer at ambient temperature. Once in the keg, drop the temperature 5-7 degrees per day slowly not to stress the remaining yeast which still have some clean up duties to perform.

Lagering and aging has benefits for many styles. It is amazing when you sample the same beer every couple weeks, they really do improve.

 

[VarangianGarde]

Just pulled a sample last night after 21 days of fermentation at ~50F ambient. SG was 1056, while reading 1014 as of last night. Thinking of waiting another week to see if the yeast is just slowly fermenting, and hoping to see an FG of around 1010.
These are great suggestions, but as of now I don't have any kegging or pressurizing setup. Once primary is complete, I plan on doing a diacetyl rest, then cold storing at about 34F in the same primary carboy. I figure this will preserve the precious CO2 layer leftover from primary, and allow an approximation of lager (while being stuck with trub at the bottom of the carboy - but hopefully storing for at max 4 weeks will not significantly affect the flavor).
What do y'all think of this plan?

 

[Beermeister32]

When the carboy cools it will pull air back into the keg. Take a empty 2 liter soda bottle and put it in the fridge to play around and experiment with what it does. Don’t rely on the CO2, it will blend with the new oxygen in the carboy. Gasses mix.

I see you are in Apple Valley. Great graphics!

If I were you, I’d head on down to More Beer in Riverside and get yourself a keg, regulator and CO2 tank. Definitely worthwhile. You will be doing it in the future, might as well do it now with this batch, why wait.

 

[MaxStout]

Even if you don't want to jump into kegging now, getting a small (5 lb) CO2 tank and regulator is still a good investment. You can use the gas to purge your fermenter, etc.

I'm a bottling neanderthal, with zero plans to keg at this time. That said, I still bought a tank and regulator a few years ago, and it's helped me make better beer. I make an occasional batch of root beer with carbonator caps and 2 liter bottles. Once you have the tank, you'll find uses for it.

 

[Beermeister32]

Or build yourself a mini setup like my office keg. 74 gram CO2 cartridge. Very handy. Lasts months. I also push full kegs with it all the time. My little buddy...

 

[MaxStout]

Or build yourself a mini setup like my office keg. 74 gram CO2 cartridge. Very handy. Lasts months. I also push full kegs with it all the time. My little buddy...View attachment 735992

I like that. What's the beer capacity?

The main reason I don't keg is that I'm the only one in the house who drinks homebrew and I just don't go through it fast enough. Plus, I don't have the extra space for a keezer. But something like that might be nice to take over to small gatherings so I don't have to schlep a cooler full of bottles. It would sit nicely in the fridge.

I take it there's a CGA320 adapter to carb from a regular tank?

 

[Beermeister32]

Me thinketh I know not CGA320 from a hole in the ground. I can say that you could carb from any CO2 tank with ball lock fittings or naturally with corn sugar. It is the same, just shorter. 2-1/2 gallons I believe.

 

[Cloud Surfer]

For all the shiny, temperature controlled things I have, one of my most valued pieces of gear is the CO2 tank, regulator and pressure transfer kit I use to do low oxygen brewing with. I use it for everything, whether cold crashing, transferring to conditioning keg or bottling keg, and counter pressure bottling.

It’s gotta be one of the cheapest ways to significantly improve your beer. I certainly saw the difference when I started using the low oxygen process.