I have always let the fermenter suck in air when cold crashing, which may not be great for hop quality. Today decided to see if I had anything I could use to hold a volume of CO2 to feed the fermenter as it chills. Being out of party balloons, I came up with this monstrosity:
That is a produce bag, a drilled stopper, and a coffee stirrer jammed in to my blowoff tube. The bag is fed through the stopper and then down around the outside before plugging it into the tube. (The coffee stirrer prevents the plastic bag from plugging up the hole in the stopper, so gas can move freely.)
I inflated the bag with a scrap of the same hose and a carbonation cap, then switched it to the sanitizer end of my blowoff tube.
I don't know how much this can really help, that plastic bag is probably highly permeable to oxygen, and the seal at the plug is probably not air-tight... but the working pressures are low and it can't hurt to try it.
So what kind of plastic bag is cheap, tough, flexible, food-safe, and impermeable to oxygen over the course of a few days? It should be possible to make something less hideous and more easily inflated and re-used.
That is a produce bag, a drilled stopper, and a coffee stirrer jammed in to my blowoff tube. The bag is fed through the stopper and then down around the outside before plugging it into the tube. (The coffee stirrer prevents the plastic bag from plugging up the hole in the stopper, so gas can move freely.)
I inflated the bag with a scrap of the same hose and a carbonation cap, then switched it to the sanitizer end of my blowoff tube.
I don't know how much this can really help, that plastic bag is probably highly permeable to oxygen, and the seal at the plug is probably not air-tight... but the working pressures are low and it can't hurt to try it.
So what kind of plastic bag is cheap, tough, flexible, food-safe, and impermeable to oxygen over the course of a few days? It should be possible to make something less hideous and more easily inflated and re-used.