# Gravity drop while bottle carbing?

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#### OneCerebralSamurai

##### Well-Known Member
How many gravity points will a cider drop when bottle carbing? How about if I want a champagne level of carbonation?

#### rycov

##### Well-Known Member
i'm not really getting what you're asking. normally gravity readings are done for fermentation not for carbing. what do you plan to prime with? are you thinking of bottling before fermentation is complete?

OP
O

#### OneCerebralSamurai

##### Well-Known Member
For example: I back sweeten a cider to 1.015 and want a regular level of bottle carbonation before I pasteurize  should I expect the gravity to drop to 1.012? 1.008? when it's reached a regular level of carbonation? Also  how much more will the gravity drop if I let it carb up to champagne levels?

Said another way  I made a batch of bottle carbed cider, and everyone seemed to like it at its FG = 1.007. If I want to make a similar batch (carbed, and with a FG of 1.007) how high do I need to back sweeten? 1.010? 1.012? What if I want a higher level of carbonation? 1.015? 1.020?

I remember reading somewhere that a cider will drop 3 gravity points when carbonating  meaning that to get a carbed 1.007 cider, I'd need to back sweeten to 1.010. This seems low to me (it seems that cider would drop more than 3 gravity points to carb), so I was asking if anyone had any additional info.

Thanks,

#### DoctorWho

##### Well-Known Member
I think it should be the same (or be so slight as to not really matter) as what ever the reading was before you bottle. The sugar you use to prime will raise the sg a slight amount but then as the yeast eat and turn out alcohol and CO2, the sg will drop back down a slight amount.

But I have never done an actual reading to confirm.

EDIT:
Ok, now I see what you are saying...You are raising the sg with sugar, bottle conditioning and then pasteurizing. That would deviate from the normal priming methods. Sorry, I am not sure as I have not done it this way yet.

#### BoxofRain

##### Well-Known Member
DoctorWho is right. The yeast ate all the sugar until you reached your final gravity. By adding priming sugar you are raising your gravity. They yeast will eat that sugar until it's gone and you will have the same gravity as before.

OP
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#### OneCerebralSamurai

##### Well-Known Member
I think it should be the same (or be so slight as to not really matter) as what ever the reading was before you bottle. The sugar you use to prime will raise the sg a slight amount but then as the yeast eat and turn out alcohol and CO2, the sg will drop back down a slight amount.

But I have never done an actual reading to confirm.

EDIT:
Ok, now I see what you are saying...You are raising the sg with sugar, bottle conditioning and then pasteurizing. That would deviate from the normal priming methods. Sorry, I am not sure as I have not done it this way yet.
OK, what DoctorWho said jogged my memory. If 3/4 cup is used to backsweeten a cider that has reached FG, and this will create a normal level of carbonation, then ~ 3 point drop is what this correlates to.

Anybody know how much more a champagne level of carbonation would drop?

What I'll probably do is back sweeten to 1.013, and then just take readings  I'll likely end up somewhere between 1.007 and 1.010 when I reach the level of carbonation I want.

OP
O

#### OneCerebralSamurai

##### Well-Known Member
DoctorWho is right. The yeast ate all the sugar until you reached your final gravity. By adding priming sugar you are raising your gravity. They yeast will eat that sugar until it's gone and you will have the same gravity as before.
Yes, I understand. However, I'm trying to not end up with a bone-dry sparkling cider. I back sweeten enough to create bottle-bombs if I don't pasteurize. I (and much more importantly, swmbo) prefer semi-sweet sparkling cider, and this is a little more complicated.

#### DoctorWho

##### Well-Known Member
I get what you are trying to do...because I've done similar. Generally, people on the board say that their sweet ciders taste best between 1.015 and 1.010.

I would say that if you want to have lots of carbonation, add 5 points (1.015-1.010.) The danger here is over carbonation + heat pasteurization. What I do is put some of my cider in a plastic soda bottle to measure my level of carbonation. I know that if it gets hard as a rock, I have let it go for too long and I have to start over! This way it doesn't really matter how precise the SG measuring is, you know when carbonation is ready and it's time to pasteurized However, I use the "normal" amount of carbonation.

Are you going to bottle in champagne bottles? I don't know anyone who has tried using regular beer bottles with lots of carb and then pasteurized. But do let me know how it goes. There seems to be a stigma against pasteurizing bottle conditioned brews. The time I did it, it worked out great!

Cheers!

OP
O

#### OneCerebralSamurai

##### Well-Known Member
The last batch I made I was expecting to have to pasteurize, but I kept opening one bottle (or 3 ) every week or so to taste and check the carbonation level, and it just leveled out at 1.007 and I never did have to pasteurize it. To me 1.007 is pretty dry, but everyone else seems to like it. (It's actually a cranberry-apple cider, and I think the cranberry astringent-ness makes it seem dryer to me.)

I've done this in 22oz beer bottles before, but since I'm thinking of upping the carbonation level, I'm thinking of doing my next batch in 12oz beer bottles because they have greater strength (also, I'll probably use Sam Adams or similar bottles which are stronger than some of the cheaper bottles I have). I'll probably keep the gravity drop to 5 points to stay on the safer side.

I do have some 16oz plastic bottles that I sometimes use for beer, and I'll likely fill a couple of these to check carbonation levels like you mention. I have been saving up some champagne bottles, but I've never bottled anything in them and I'm a little uncertain how to go about it.

#### DoctorWho

##### Well-Known Member
I think you'll be fine and you've done it before, so less worries!

If the champaign bottles are american you can put a standard 26mm crown cap on them and bottle as you normally would. They are much thicker and can take more pressure. Apparently, european bottle need a larger crown cap. I am going to start save a few myself.

#### rycov

##### Well-Known Member
ok. i see what you're doing. i don't know too much about it, but if i were doing it, well i would keg it, but other than that, i would use splenda, or lactose or some other unfermentable sweetener. just to eliminate the risk of bombs. sorry for my lack of understanding earlier

OP
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#### OneCerebralSamurai

##### Well-Known Member
Update  just in case anyone comes across this thread and has questions:

I've determined that champagne-level of carbonation (~7 volumes of CO2) is on the order of three times that of regular cider carbonation (~ 2.5 volumes of CO2). I would therefore categorically advise against trying to get anywhere close to champagne-level in 12oz beer bottles... (Unless you are deliberately doing a science experiment on the velocity of glass shards:rockin.

Note that "volumes of CO2" does not directly correlate to PSI, but the trend is close enough to draw broad conclusions.

I will be keeping my carbonation experiments to 4 or 5 gravity point drops at the most  and then only in the strongest bottles I have. Anything greater than that will only be done in champagne bottles.

#### Sardoman

##### Well-Known Member
Thanks for the update. I was searching for threads with info on carbonation levels and pasteurization. Too often people leave threads dangling with no conclusion and it was thoughtful of you to return and finish this one.