How To Calculate The Final PSI For Sparkling Drinks

[evenstill]

I want to make some sparkling wine/mead but haven’t been able to find any information on how to calculate the final PSI. I’ve been told that around 2 atmospheres of pressure (around 30 PSI) is about average for a beer which is roughly the amount of sparkle I’m trying to achieve. If I’m using yeast with an alcohol tolerance of say 14% and I put just enough sugar in to reach 12% then prime with the rest of the sugar needed to reach 14% alcohol per volume and bottle will that 2% APV give me the desired pressure (30PSI)? Does anybody know how to calculate exactly how much pressure is built up with each percentage point of alcohol per volume or where I can find this information? Is there anywhere to find out exactly how much CO2 each strain of yeast produces with each percentage point of alcohol per volume?

Thanks,
evenstill

 

[Gedvondur]

You are overthinking this a bit.

If you prime it and bottle it they will come out "sparkling". You are not really looking for a PSI pressure since you can't measure it anyway.

Prime it, bottle it, and wait. If you overprime the bottles will explode. The only time you concern yourself with PSI measurements is when using a draft system.

I imagine your mead will need about a cup of corn or some other kind of sugar for 5 gallons. Not sure on that, perhaps wiser heads will have a better answer in the case of mead.

I would not just use "the rest of the sugar" to get it to 14% abv. That will either undercarbonate, or more likely result in bottle bombs. Let it ferment out to where ever it stops, add priming sugar and bottle. The yeast tolerance for alcohol is an estimate anyway. There is no need to be that precise.




Gedvondur

 

[evenstill]

Here is some very useful information I found that will help you achieve safer, more consistent results. Enjoy!

4g of sugar per liter of wine will produce approximately 1 standard atmosphere (atm) of pressure (15 psi) and 0.216% additional alcohol.

From the UC Davis course "Introduction to Winemaking":
“The amount of sugar that is added will determine both the final CO2 pressure and the amount of additional alcohol that will be produced. (Approximately 1 atmosphere of pressure will be generated by 4g of sugar per liter). Thus to produce 6 atmospheres of CO2 will require 24g sugar per liter of wine. This much sugar will result in an additional 1.3% alcohol (2.4% sugar x 0.55).”

From A Primer on Priming:
“Determining the amount of priming sugar is based on the fact that adding 4 grams of sucrose (cane/beet/granulated sugar) per liter will ferment to give 1 volume of CO2: 4 g/l (1/2 oz/US gal) sucrose --> 1 vol. CO2.”

http://www.meadmadecomplicated.org/mead_making/recipes/sparkling.html

http://www.geocities.com/lumeisenman/chapt20.html

Luck,
evenstill