Coffee beans release CO2 after roasting due to thermal processes. This CO2 release goes on for about 10 days after roasting, with about 80% released after 48 hours. We seal our roasted coffee in Mason jars 24-48 hours after roasting it in cast iron. This means about 20% of the CO2 will be trapped in the jar, slightly pressurizing the jar and displacing Oxygen with CO2. This gives our coffee that signature “pop” when you open the jar, and prevents the beans from oxidizing, keeping them fresh.
For a much more detailed overview on what makes our coffee different, read this post