Oxidation

[doug293cz]

Lets say you push 2000Litres of carbon dioxide through a 19L keg that atmospheric 21% oxygen concentration will be diluted to about 0.2%

This is still quite high with respect to oxygen concentration in CO2. Normally for oxygen concentration we would aim to have be 0% to at least 2 decimal places. The ISBT specification for oxygen concentration in beverage grade gas is sated to be 30ppm.

If on the other hand you fill the keg with liquid firsts and displace with CO2 then you should get below the 30ppm threshold.

Read this post above, and the linked post. The theory has been presented and verified experimentally. Your math is for mixing 2000 L of CO2 with 19 L of air all at once. The fact that the dilution takes place gradually, over time, makes a huge difference.

Edit: The fact that the final volume is 20 L, rather than 2020 L, and most of the gas gets pushed out of the keg is also a big part of the difference. (Actual enclosed volume of a corny is closer to 20 L than 19 L.)

Brew on

 

[IslandLizard]

Your math is for mixing 2000 L of O2 with 19 L of air all at once.

I think you meant to write CO2, not O2...

 

[doug293cz]

I think you meant to write CO2, not O2...

Yes indeed. Corrected. Thx.

Brew on