Bulk Aging & solid bung?

[Elmer]

Just got off the phone with wine support at WineXpert.
I had a question or 2 about thier directions, their kits and a little compliment about the women who works at the order desk.

I expressed my concern that since I had to fully degass prior to the clarifying stage, I was worried that there would be no gas to protect the wine in the air space since the 6 gallons of wine is in a 6.5 carboy (and they say not to top up yet).

She reassured me that the wine will be fine during the process.
However she indicated if I intend to bulk age to top up and use a solid bung with the carboy.
I explained that I have always used a stopper and airlock.
She indicated that if I have fully degassed and cleared that only a solid bung would seal the carboy off from O2 making its way in.

When I countered that I thought a stopper and airlock did the same, she reassured me that they have done many test and trails and a solid bung is the way to go.

I have never heard this before.

Anyone go this route?

Thoughts?

 

[salcoco]

if you are past the three month stage on the wine a solid bung is fine.

 

[bkisel]

They're a reputable kit wine manufacturer. What they said to you makes sense to me especially if they've done test and trials.

So how long do they have you not topping off? And is this while in "secondary" phase?

 

[sour_grapes]

Tim Vandergrift says that using a solid bung after 90 days will "further reduce the chances of oxidation." In a followup article, he says that even a solid bung is much leakier than a cork, so bottling is probably better than bulk aging.

As for an airlock: it will certainly pass O2. Let's say some O2 in your headspace reacts with something in your wine. This will reduce the partial pressure of O2 in the headspace. There will then be a net diffusion of O2 that is dissolved in the water of your airlock from that water to the headspace. There will then be a net diffusion of O2 from the atmosphere to the water of your airlock. In other words, an airlock is permeable to O2. I don't know, however, how much the diffusion of O2 is slowed by the water; it could be that the diffusion takes a long time, and so the airlock is effective in reducing oxidation.

 

[Elmer]

They're a reputable kit wine manufacturer. What they said to you makes sense to me especially if they've done test and trials.

So how long do they have you not topping off? And is this while in "secondary" phase?

I am in the last stage of secondary, step 3 where you stir up all the sediment and add the clarifyer and degass.

They dont have you rack out of secondary for another 8 days, then top up.

but since my carboy is in my basement (only available spot) it is about 65 degrees, which they want me to keep it around 72. otherwise they indicate that clearing will take longer, extending my 8 days.
I have a brew belt on and just might wrap in a couple thick blankets in hopes of warming up

 

[bkisel]

The instructions I got with my brew belt cautioned against covering the belt. I'm thinking you can put the belt very near the bottom of your carboy and affix the blankets with a bungee cord or something to prevent covering the belt.

Oh, BTW just finished using my belt for the foist time in fermenting an RJS kit wine. Basement temp was ~60F and must was about ~74F with the belt positioned low on the bucket and then the "secondary" carboy. Also, initial must temp from kitchen warmed juice and warm water and then fermentation kicking in kept the temp up there for a few days before I needed to add the belt.

 

[JohnT]

Here is the question we all should be asking...

How much head space do you have right now?

If you have your carboy filled to within 1 inch of the stopper, then you have NOTHING to worry about when it comes to oxidation. The amount of O2 that will pass into your carboy will be negligible and could also be beneficial at that level to help mature your wine.

I have had full carboys under a stopper and fermentation trap for up to 5 years and they have turned out just fine. The key here is to keep them filled.

 

[Elmer]

Here is the question we all should be asking...

How much head space do you have right now?

If you have your carboy filled to within 1 inch of the stopper, then you have NOTHING to worry about when it comes to oxidation. The amount of O2 that will pass into your carboy will be negligible and could also be beneficial at that level to help mature your wine.

I have had full carboys under a stopper and fermentation trap for up to 5 years and they have turned out just fine. The key here is to keep them filled.

I currently have 1/2 gallon of headspace.
I have 6 gallons of wine, in a 6.5 gallon carboy.
The WineXpert women said this is find because I am still in secondary!

 

[ibglowin]

Solid stoppers certainly have their place. Yes they are much better than an airlock at preventing O2 from getting in or out and not as good as a cork. With that said remember that the expansion of alcohol with temperature is quite large! If the temps in the winery are falling then the wine is contracting and occupying a smaller space (less pressure on a closed vessel) If the temps are rising or…… you put a brew belt on, then the wine will expand with increasing temp. If you have a stoppered wine and add the stopper at say 60 degrees and then the wine warms up to 70 degrees you have a nice little rocket waiting to explode out the top to relieve the pressure. I would use the airlock until you have the wine stabilized and cleared (a week or so) then remove your brew belt, let the temp fall and add the stopper. If the temps start to rise, even a few degrees, you need to crack the stopper and release the built up pressure that has formed or…. it will release itself sooner or later!

 

[bkisel]

Would a balloon or maybe saran wrap over the carboy neck provide both a seal and a way to handle temp/pressure changes? I use use saran wrap on my stored empty carboys that have been spritzed with k-meta. I'll notie that at times the warp is sometimes bulged out and other times con-caved in due to pressure changes.

From WikipediA... "When formed into a thin plastic film, the principal advantage of Saran, when compared to other plastics, is its very low permeability to water vapor, flavor and aroma molecules, and oxygen. This oxygen barrier ******* food spoilage, while the film barrier to flavor and aroma molecules helps food retain its flavor and aroma."

 

[richmke]

I am thinking of the vented silicone bung for bulk aging. Lets the pressure out, but not let anything back in.

I am trying to figure out the science of oxidation of wine in the carboy.

1) The bung will let the same amount of O2 through, regardless of the head space in the carboy.
2) The more head space, the larger the surface area for the O2 to dissolve faster into the wine. Also, the more head space, the more initial O2 in the carboy when you stopper it.
3) I think gas expands more when heated, so more head space would make the carboy more sensitive to temp changes, and to changes in air pressure.
4) C02 is heaver than O2, so it provides some protection against oxidation.

I think the last reason is why WE testing showed you do not have to top off the carboy.

Seems to me that if you use a keg charger (nifty idea from the wine 101 class at the LHBS), you can displace most of the air in the carboy with CO2. Then stopper it, and you are good to go for a while. You don't have to top off the carboy. The local LHBS uses nitrogen, which is even better because it is heavier.

The keg charger trick is also good when bottling wine. Expel all the O2 before corking.

 

[Putterrr]

I am thinking of the vented silicone bung for bulk aging. Lets the pressure out, but not let anything back in.

I have had good success with the vented bungs from vintable.com

cheers

 

[sour_grapes]

The local LHBS uses nitrogen, which is even better because it is heavier.

Your other comments and observations seem correct to me, but nitrogen (N2) is lighter than oxygen (O2) and much lighter than carbon dioxide (CO2).

 

[ibglowin]

Why would you want to add something (CO2) back to a wine that we as winemakers try so hard to get rid of in the first place? CO2 can and will diffuse back into a wine if you fill a headspace with it and stopper it.

 

[ibglowin]

Density of Air: 1.29 g/L

Density of Nitrogen: 1.25 g/L

Density of Argon: 1.63g/L

Density of CO2: 1.96 g/L

 

[richmke]

but nitrogen (N2) is lighter

Forgot to check that. Darn. Skip the nitrogen.

Why would you want to add something (CO2) back to a wine that we as winemakers try so hard to get rid of in the first place? CO2 can and will diffuse back into a wine if you fill a headspace with it and stopper it.

You are not pressurizing the head space. You are trying to displace the O2 in the head space. Something has to take up the space. Better to have CO2 than O2. You would much rather have the CO2 diffuse back into the wine than O2.

 

[ibglowin]

I use Argon for just that purpose. Short term backfilling of the headspace.