Specific Gravity relationship to Volumes of CO2?

[lukebuz]

If I bottle of wine or cider (that I intend to make sparkling) at a certain specific gravity - is there any relationship to how much carbonation I'll have?

Let say I put an 13.5% apple wine, that reads 1.005 on the hydrometer in a champagne bottle. Pitch Premier Cuvee Yeast starter, so it should ferment it all. What amount of carbonation will I have at the end? Volumes of CO2?

Thanks!

 

[Thunder_Chicken]

Don't attempt this, it is difficult to control and not safe. The gravity change to properly carbonate your wine is only 2-3 points. Fermentation does not have to stop at 1.000 - many wines will go down to 0.990. If that were to happen with your wine you would have over 10 points of gravity converted to CO2, a sure recipe for bottle bombs, even in Champagne bottles.

Let your apple wine ferment out to dry. It may take a while for the last few points to dissappear. Once it is dry and stable, then prime with an appropriate amount of sugar and bottle.

 

[lukebuz]

Don't attempt this, it is difficult to control and not safe. The gravity change to properly carbonate your wine is only 2-3 points. Fermentation does not have to stop at 1.000 - many wines will go down to 0.990. If that were to happen with your wine you would have over 10 points of gravity converted to CO2, a sure recipe for bottle bombs, even in Champagne bottles.

Let your apple wine ferment out to dry. It may take a while for the last few points to dissappear. Once it is dry and stable, then prime with an appropriate amount of sugar and bottle.

Well, crap. It's too late, as I've bottled quite a bit like this already. How long before bottle bombs might present themselves?

 

[Thunder_Chicken]

When the glass decides it's had enough stress and fails. Within days possibly. Glass is a strong material but it will generally fail at a flaw, so it is difficult to predict.

I'd uncap / uncork them all ASAP. Then cover each bottle with sanitized cling wrap and hold it in place with a rubber band. Wait until the gravity stabilizes (might be a while), then carbonate with coopers drops.

Do this NOW!

 

[WilliamSlayer]

A drop of aprox. .006 on your hydrometer creates 2.5 atmospheres of CO2 pressure.(an American level of beer carbonation)

Most champagnes are carbonated to around 3-4 atmospheres.

A standard beer bottle can withstand around 3-4 atmospheres.

A standard champagne bottle should withstand about 5 atmospheres.

 

[Thunder_Chicken]

A drop of aprox. .006 on your hydrometer creates 2.5 atmospheres of CO2 pressure.(an American level of beer carbonation)

Most champagnes are carbonated to around 3-4 atmospheres.

A standard beer bottle can withstand around 3-4 atmospheres.

A standard champagne bottle should withstand about 5 atmospheres.

That assumes you don't have any CO2 dissolved in the wine at the start of the process. 3 points is more typical for 2.5 volumes.

 

[MaxStout]

Uncap those bottles as soon as you can. You can also put small pieces of sanitized foil over the tops while they outgas. The above advice here is rock-solid, and we don't want to later read about some catastrophe. There are plenty of stories about bottle bombs, usually involving pulling glass shards out of walls and ceilings. I've never witnessed one personally, but have heard it's like a cherry bomb going off in a bottle.

 

[WilliamSlayer]

That assumes you don't have any CO2 dissolved in the wine at the start of the process. 3 points is more typical for 2.5 volumes.

Yup, that's true.

 

[lukebuz]

Great, thanks for the advice!
All carbed drinks are in a crown capped bottles - I saw on the net about cracking the caps open slightly, letting them degas, and then re-crimping shortly afterwards.
Any advice on that? Think it's OK to recrimp in this instance? I'd really rather not let some of these batches go dry, and then add to recarb, as I'll be looking at 15%abv. Yikes!

 

[MaxStout]

You could use the slightly-opened caps as temporary covers that let out CO2. But when it's time to re-cap, you should use new caps, as the old ones might not seal up properly.

 

[Thunder_Chicken]

Great, thanks for the advice!
All carbed drinks are in a crown capped bottles - I saw on the net about cracking the caps open slightly, letting them degas, and then re-crimping shortly afterwards.
Any advice on that? Think it's OK to recrimp in this instance? I'd really rather not let some of these batches go dry, and then add to recarb, as I'll be looking at 15%abv. Yikes!

You must let these bottles ferment to completely dry with their caps off. You can't just vent gas and then immediately recap as there will still be sugar that the yeast will continue to ferment and make CO2. The yeast will ferment that cider to dryness whether you cap it or not. Capping does not stop the fermentation process.

In the future, know that there are methods to safely carbonate a sweetened cider. One is to ferment the cider to dry, then backsweeten with a non-fermentable sweetener like Splenda, then prime and carbonate as usual. This is a safe way to make sweet sparkling ciders.

A more advanced (and risky IMO) method is to bottle pasteurize a sweet cider when it reaches the proper level of carbonation, but this method requires a clear understanding of the carbonation process, and requires a means to monitor carbonation. This must be done very carefully, as heating overcarbonated bottles can easily produce bottlebombs (and they'll explode in your face as you are handling them, not good). I am comfortable with naturally carbonating beers and wines, but the idea of bottle pasteurizing scares the willies out of me.

 

[WilliamSlayer]

you could use the slightly-opened caps as temporary covers that let out co2. But when it's time to re-cap, you should use new caps, as the old ones might not seal up properly.

+1

 

[lukebuz]

Well, for the batches bottled at a SG of 1.004-1.005, they bubbled and bubbled an bubbled for about 2 hours before I was able to pry the caps off totally and recap. Again, I don't know just how much more fermenting is left to go (they were bottled about a week ago, kept at 68-70*), but they were WAY WAY WAY overcarbed.
From now on, I'll do it right...and just pray the current batches are OK! Or, when I open one, if they are still mega-carbed, then repeat the process...sigh...

 

[Thunder_Chicken]

Don't recap now! There is still an unknown amount of sugar in those bottles!

 

[lukebuz]

Yup, I know there is. For now, I"m going to risk it (again, thanks for the proper way, I'll do in the future) and let them go for now. When I open one again, if it is overcarbed, then I'll bleed off again. I'll check one in a week or so.
I know it's not proper...but this is a salvage mission, really.

 

[Thunder_Chicken]

Don't wait a week to check! A couple of days is more than enough time to produce carbonation.

 

[WilliamSlayer]

Don't wait a week to check! A couple of days is more than enough time to produce carbonation.

+1

Yes, been lucky and only had one incident like this but you do not want to let this get away from you.

EDIT- sorry for the extra photos, the bottles should have been the only one attached!

 

[ihavenonickname]

I did a little research on this. All the information is out there of course, I'm just putting a few ideas together:

A critical assumption is that you have reached final before closing the bottle or the keg. Or at least that you know exactly what the FG is going to be (very difficult to predict as others have pointed out)

At 80F (my summer time temp) the finished beer going into the keg is holding onto 0.7 vols of co2. Adding 4.4oz of sugar would get it up to 2.5 vols co2. This equates to ~0.002 gravity points.

So bottling with more than 2 gravity points left is where is starts to get risky!

But I can also use this to my advantage: It makes sense to do some natural carbing in the keg for 5 days or so while my keg hops saturate at room temp. It should help purge oxygen and the added vols (by adding about 4 oz of sucrose to my keg) will make my burst carb in the keg quite a bit faster!

Cool!