how much psi in conditioning bottles?

Pressure, measured in pounds per square inch, is defined as the force at which the CO2 molecules in the head space of the keg push on the beer. As the pressure increases, the gas hits the beer with more force and dissolves into the beer more easily. As the pressure decreases, the gas does not dissolve into the beer as easily and gas can come out of the beer.

High pressure increases the carbonation level, low pressure reduces the carbonation level. The right amount of pressure in a keg will maintain the right carbonation level.

Most breweries or distributors can give you suggested pressure settings for the beers they sell. If you make your own beer use a carbonation chart to determine the proper pressure.

Temperature and CO2 Balance

The temperature of the beer effects the amount of pressure needed in the keg to control the carbonation level. As temperature increases, CO2 bubbles expand and will come out of the beer. As temperature drops, CO2 dissolves more easily into the beer.

For example, at 38 degrees F, Coors Light needs 15 psi to maintain its CO2 level. At 40 deg F it needs 16 psi. At 36 deg F it needs 14 psi.

Generally, a two degree increase in temperature requires a one pound increase in pressure. A two degree decrease in temperature requires a one pound decrease in pressure.

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Style & Volumes of CO2
American ales 2.2–3.0
British ales 1.5–2.2
German weizens 2.8–5.1
Belgian ales 2.0–4.5
European Lagers 2.4–2.6
American Lagers 2.5–2.8

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Revvy said:

In natural bottle conditioning we talk about Volume of CO2. The amount of gas dissolved into beer is measured in volumes. If one liter of beer is carbonated to 2.5 volumes, then there are 2.5 liters of CO2 gas dissolved into the beer.

In a typical beer that is bottle carbed w 5 ounces of sugar @ 70 degrees provides 2.5 volumes of co2. It's going to be 2.5 volumes of co2 regardless of whether ir is in a 12 ounce bottle or a 1 gallon jug (which I hope you aren't planning to bottle you beer in a 1 gallon jug, it is not made to handle the pressure of carbonation.

We only really talk about PSI in terms of force (keg) carbonation, not bottles.



Many Styles are carbed higher than the standard 4.5- 5 ounces of sugar/2.-2.5 volumes of co2 that comes with basic kits, and often that is more sugar than that. Think of belgian beers for instance, or some pilsners, or Autralian sparkling ales. They are all carbed higher than most basic beers, and except for beligians are often bottled in normal bottles and they don't gush or explode.

You can just look at beersmith and see the different amounts of sugar needed to carb by style.

For example the style volume of co2 range for an Australian Ale is 2-2.8 volumes of Co2, and if the beer is @ 70 degrees at bottling time, then you would need, 6.12 ounces of sugar if you wanted to carb at the highest volume for that style.

hat 4.5 - 5 ounces really just tends to be the baseline for most gravity/ styles of beer, (when bottled at 70 degrees) but there are plenty of styles that use less or more sugar to be less or more carbed than that.

Here's the volumes of co2 for most beer styles...you can see how high Belgians and German weizens can be carbed.



A basic 12 ounce beer bottle, or as it is called the Longneck Industry Standard Bottle (ISB) can actually hold around 4 volumes of co2 without breaking. I can't find the numbers, but it IS greater than the normal 2-2.5 volumes of co2, it may even be 5 volumes. for safety reasons it would have to be much greater than the normal volume of co2 a beer is primed at. They are going to vary obviously in wall thickness. But NORMALLY they won't burst, unless as mentioned repeatedly you waaaay over prime, waaaay over heat, or have an infection.

Hope this helps.

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grathan said:

On average. Assuming completed fermentation and approx 5oz dextrose thouroughly mixed into 12oz bottles and also 1 gallon bottles.

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