I recently gave a listen to the Brulosophy podcast episode on reducing cold side oxidation, and in an effort to improve my processes, I keep coming back to one of their suggestions on collecting fermentation CO2 for later use in kegging or cold crashing. I'm hung up on one aspect, however, and I was hoping someone had some experience with it.
One of the guys' suggestions for reducing oxidation at kegging, was to package into a CO2-filled/purged keg. To do this without wasting a ton of purchased gas each time, they suggested collecting CO2 from fermentation by means of first filling a keg of star-san, then having fermentation push that out, thus filling the keg for later use.
The issue eating at my brain is this: can the pressure of fermentation actually move 5 gallons of liquid from a keg somewhat easily? If it can, how much back-pressure would 5 gallons of liquid generate and would it have an impact on fermentation? I would imagine some yeast strains are more susceptible to back-pressure (can't remember if it was a specific saison strain, Denny's Fav, etc.), as i know there are a number of accounts of people needing to ferment without an airlock to prevent a stall.
One of the guys' suggestions for reducing oxidation at kegging, was to package into a CO2-filled/purged keg. To do this without wasting a ton of purchased gas each time, they suggested collecting CO2 from fermentation by means of first filling a keg of star-san, then having fermentation push that out, thus filling the keg for later use.
The issue eating at my brain is this: can the pressure of fermentation actually move 5 gallons of liquid from a keg somewhat easily? If it can, how much back-pressure would 5 gallons of liquid generate and would it have an impact on fermentation? I would imagine some yeast strains are more susceptible to back-pressure (can't remember if it was a specific saison strain, Denny's Fav, etc.), as i know there are a number of accounts of people needing to ferment without an airlock to prevent a stall.