Pressure limit of bottles - Bottle conditioning

Hi All.

After coming across a Belgian website that sold Duvel-style bottles I have some questions about the maximum carbonation limit of bottles.

Having read posts in the forum stating that the max limit of most bottles is 3 units of CO2 I was a little confused by the email I received from the website.
Here is the reply I got:

> Hello,
>
> More important than carbonation limit is the max pressure of the bottle. Most bottles (also steinie)can handle a max pressure of 4 bar. Carbonation limit can be very high, because the Co² dissolves in the beer and causes no pressure.
>
> For example : beer at 4 bar and 25 °C has a carbonation level of 7.5 g/l
> beer at 2.3 bar and 5 °C has a carbonation level of 9
> g/l
>
>
> Best regards,
>
> Roland Vanderlinden
> BROUWLAND

Click to expand...

Does this mean that I can achieve I higher carbonation than 3 units of CO2 even though I am bottle conditioning to achieve my desired carbonation?

I find it odd that the dissolved CO2 does not add to the pressure. I thought this was the whole reason why bottle bombs occur. More CO2 = more pressure and exploding bottles.

How do you know what pressure your beer is at if you are bottle conditioning?
If this guy is right than it implies that I can achieve a higher volume of CO2 as long as I do not go above 4 bar pressure. Is this possible?

Many thanks, Andrew.

I think I can clear up a bit of confusion for you.

axp said:

I find it odd that the dissolved CO2 does not add to the pressure. I thought this was the whole reason why bottle bombs occur. More CO2 = more pressure and exploding bottles.

How do you know what pressure your beer is at if you are bottle conditioning?
If this guy is right than it implies that I can achieve a higher volume of CO2 as long as I do not go above 4 bar pressure. Is this possible?

Click to expand...

Here's your quick and dirty overview of thermal physics:
Pressure is the result of gas molecules bouncing off of things. Heat increases the energy of gases, and therefore increases pressure because gas molecules bounce faster. In addition, more energetic gas molecules are less likely to stay in solution, but the more pressure there is "outside", the more likely they are to stay dissolved.

In plain terms- dissolved CO2 does not contribute to pressure, but if you have a "lot" (and here a "lot" depends on the bottle) of dissolved CO2, make sure to keep it cold.

For the belgian-style heavy bottles, you should be able to get away with 4 volumes. With regular glass, stick to 2.8 or so. Make sure the beer hits FG before you bottle, and pick up the free trial of Beersmith. It has a tool that allows you to account for the CO2 already dissolved in your beer.

Pressure will change as a function of temperature. If you put a bottle carbed to 1.5 volumes in an oven at 300 F, it'll explode in a hurry. The simple reason is that dissolved CO2 is not gaseous and adds little pressure to the bottle. The lower the temp. the more CO2 dissolves into solution.

Thanks for the replies. So does that mean I can achieve I higher degree of carbonation if I bottle condition at a lower temp?

Lets say I prime my bottles to achieve 5 vols of C02, could I avoid bottle bombs if I keep them at low temp, say 10C rather than room temp?

I have been using beersmith and promash to calculate the sugar required for 3 vols of CO2 when beer fermented at 20C. Those programs are great. The problem was that I felt the carbonation level was below that of the style I was going for. I therefore wanted to go to 4 vols of CO2 but was afraid of exploding bottles.

Just a thought, if I FORCE CARBONATED at low temp to a high carbonation level such as 5 vol CO2 and kept at low temp I would be able to avoid explosions?

Cheers, Andrew.

the lower you go in temperature the slower carbonation will occur (this has to do with the yeast producing CO2 from your priming sugar)

I think this would work and you would be alright doing it that way but maybe some others can join in with some more advice. I would try 4 volumes and make sure you leave the proper amount of head space in your bottles.

I'll have a go at 4 next time I'm bottling. With the Duvel style bottles this hopefully will not be problem as BLAM states that Duvel is carbed to ~4.5 I think.

Usually leave about 1 - 1.5 inch space from top of bottle. I think that is ok?

Thanks for the replies, have been very informative.

Cheers, Andrew.