Degassing Questions

[OldBanjo]

I've been making red kits and, though flavor has been good, I suspect it could be improved with more thorough degassing. (Getting small bubbles where the wine surface meets the glass. Amount of bubbles decreases the longer the bottle has been open.) I've been agitating with the drill attachment that came with my original kit. I've added more carboys but still need to keep bulk age time in the 6-8 week range.

Question 1: Do I need to worry about oxygen introduced during the agitation? If not, I'll stir longer.

Question 2: Would I be better off using a wine whip instead of my current device which consists of a metal rod with 2 plastic wings on the bottom? It seems to do a great job of mixing but is prone to forming a whirlpool.

Question 3: How long would I need to bulk age to avoid the pain and uncertainty of agitating?

 

[cmason1957]

I believe you do need to be aware of the amount of oxygen you are introducing. Particularly, if it is a white wine. I think the best doll mounted wine will I have ever used is the three prong who that expands as you spin it. When I used it, I went one direction until I just started to see a depression of the wine at the surface, then switched to the other direction. Wineries never do a degassing step, generally the will age a wine a minimum of one year, before bottling.

 

[user 36973]

Question 1: Do I need to worry about oxygen introduced during the agitation? If not, I'll stir longer

Yes, you always risk introducing oxygen when you whip you wine. I'm not a fan of it.

Question 3: How long would I need to bulk age to avoid the pain and uncertainty of agitating?

Racking and time (few months?) will degas the wine. Of course racking poses risk of oxidation also if you don't keep up on the sulfites.

For me, I never degas. Though I filter the wine and that process removes a lot of co2.

If you have a tank of nitrogen, you could drop a tube to the bottom of the carboy and bubble some n2 into the wine. This agitates it to remove the co2 without introducing oxygen

 

[jbo_c]

At cool temps, wine in a carboy will not necessarily degas on its on at atmospheric pressure. I have had multiple batches sit at 65 degrees for over a year and still contain fairly significant levels of gas. (Sealed barrels will create a vacuum and, so, help themselves degas.)

Warmer temps and racking will help, but I always do some physical(whip) degassing even though I’m also not a fan. I use vacuum after an initial degassing.

For some reason, kits seem to hold on to gas more tenaciously. I have no science behind that, but my personal experience says it’s undeniable.

Jbo

 

[OldBanjo]

I've now been agitating a batch for over 40 minutes I'm still getting a blanket of very fine bubbles. Does it make sense that CO2 can still be coming out or am I just pulling out SO2 or O2 that has gotten stirred in??? I'm about to throw my drill against the wall and take up knitting!

 

[jbo_c]

If it fits my idea of blanket and fine bubbles, I’d say you’re still getting CO2, but I’m not sure about the ‘blanket’ description.

What temps?

 

[OldBanjo]

Its at 74 degrees. I've also already added sorbate and k-meta.

Here's a more detailed description of the bubbles. Whenever I would take a break from drilling, they would look like specks working their way along the surface of the carboy to the surface. On the surface, they would form a layer about 1/2 inch thick. If anything, I was getting more bubbles as time went on.

 

[DoctorCAD]

Are you sure the wine is done fermenting?

 

[jbo_c]

Hmm. At 74F I’d think it should degas fairly readily. Are you sure you’re not whipping it into a froth? That wouldn’t be good(or a symptom of CO2). But that sounds like a lot of off gassing if you’ve really been doing it that long. I wonder if you’re whipping the wine.

Try the poof test. It should be pretty obvious if it’s gas at the level you’re describing.

Jbo

 

[rustbucket]

Once you degassed the wine to the extent you have, leave it in the carboy for a month. The rest of the gas will generally have dissipated by the end of that period. Following that, add a quarter teaspoon of potassium metabisulphate to the wine before bottling.

 

[Rice_Guy]

I've now been agitating a batch for over 40 minutes I'm still getting a blanket of very fine bubbles. Does it make sense that CO2 can still be coming out or am I just pulling out SO2 or O2 that has gotten stirred in??? !

SO2 should not be at a level where you would see bubbles. If you did you would be coughing and choking.
There is a risk that you could have wiped air in. If so it should stop fairly quickly after agitation. Probably would not be the fine bubble you describe since most of the air is not dissolved in the wine (dissolved O2 at 74F is about 5.5 ml per liter)
At 6 weeks/ 74F I would expect fermentation to be done. Residual CO2 will produce a froth if you take a half full baby food jar and shake it, a guess is if you test this you have some foam.
A low vacuum (5 inHg) can be generated with a home vacuum cleaner. When I have done this I put a single hole carboy cork on the suction and run tubing to the carboy with another single hole cork, and let it run for a few hours. , , loud , , , but unless you have a harbor freight vacuum pump this gets it done.

 

[OldBanjo]

Did the poof test and its definite acting like CO2. Tasted a bit fizzy, too.

I think this may be a good time to try out some of the vacuum methods. Thanks, Rice_Guy for outlining a system I can try without spending more $$$.

If I can get a vacuum system to work, is there a downside to using prior to bottling to take care of any excess CO2 that bulk age didn't take care of. (I have another batch aging that is probably pretty gassy too.)

 

[sour_grapes]

If I can get a vacuum system to work, is there a downside to using prior to bottling to take care of any excess CO2 that bulk age didn't take care of.

Nope, that is a fine way to proceed!