Seeking wild conjecturing …

[Cider Wraith]

...already fully fermented - 2 gals sweet apple 2 liters mixed sweet juices

.... looking good, planning transfer to corny

Question - after unavoidable open-air auto-siphon transfer to open-top corny, before resealing corny, thinking about adding additional gallon of sweet apple to mix. Receiving corny would then remained sealed after transfer.

What will happen? Maybe something like 3 PSI or nuclear detonation?

 

[bracconiere]

Maybe something like 3 PSI or nuclear detonation?

i'd guess dangerous? overcarbed probably at least....

 

[Cider Wraith]

i'd guess dangerous? overcarbed probably at least....

Thank you for replying ... so it's a crazy question ... could one additional gallon of sweet apple applied to an existing three gallon batch raise to over 130 PSI?

 

[bracconiere]

at ~28g's of sugar a 8oz glass, and a gloon...here's what the priming calc says...

 

[doug293cz]

at ~28g's of sugar a 8oz glass, and a gloon...here's what the priming calc says...

View attachment 779216

Clever way to do the analysis, but unfortunately you used one of the brain dead calculators that ignores the principles of chemistry, and thinks you get twice as much CO2 per gram of sugar if you carbonate in a keg vs. a bottle.

OP has 3 gal + 2 L = 3 * 3.78541 + 2 = 13.4 L of cider with 28 * 16 = 448 g of priming sugar. 1 g of fructose or glucose will create 0.49 g of CO2 when fermented, so when conditioning is complete you will have added 218.9 g of CO2. Your cider is probably starting out with about 16.1 g of residual CO2 after primary fermentation, so at the end the keg will contain 218.9 + 16.1 = 235 g of CO2. This CO2 will be distributed between the cider and the headspace. A keg has a volume of 20 L, so your headspace will be 20 - 13.4 = 6.6 L. The distribution of CO2 between cider and headspace, and the headspace pressure will depend on the keg temperature. Solving this all requires a spreadsheet and the Goal Seek function so I won't show the details here, but let's assume you condition the keg at 70°F, and the headspace starts out as 100% CO2 at 0 psi gauge pressure. I come up with a final headspace pressure of 51 - 52 psi gauge pressure, and a carbonation level of 7.1 - 7.2 volumes (that's hella fizzy.)

Brew on

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[bracconiere]

ahh i'll keep that in mind...

edit: damn i didn't even really notice the difference in sugar weight bottling vs kegging, just wanted the psi....

 

[Cider Wraith]

Holy Moly, Batman @doug293cz that's one heluva answer... ok, clearly too dangerous to fool with without "spunding" valve or air lock ... thanks for the reply