Yeah, that’s great info and backs up Ken’s point. I’d just never tried to pump much carbonation into my ciders so it had never been an issue for me. Makes sense about beer often having a lot more CO2 in solution.
wort-h.o.g
January 30, 2015, 6:52pm
22
Funny how we stumble across stuff sometimes huh [emoji16]
Hey - I found the post. I just needed the right frame of mind I guess because I thought it was lost to the interwebz. I’ve been trying to find it for a while.
Full thread - https://groups.google.com/d/msg/cider-workshop/a_AznLMoSOc/cQig2jv72gIJ
I’ve done a few more calculations now … According to Henry’s Law, saturation CO2 at 45F (7C) is around 1.25 vol.
Going back to the previous posting for that condition, we had a shortfall of 1.5 vol at an indicated 3 vol carbonation. So if the beer or cider is just saturated with CO2, the sum of these now gives a
Taking another example, at 75F (25C) 5 oz of sugar per 5 Gallons is shown by the nomograph to give 3 vol carbonation. That amount of added sugar is (528)/(5 3.8) = 7.4 g/L which will give 3.7 g/L of CO2. That is around 1.85 vol of CO2. Henry’s Law shows that at 75F the saturation of CO2 is 0.75 vol. Putting those together we get 2.6 vol, a shortfall of 0.4 vol.
In either case there is a calculated shortfall which is presumably made up by the supersaturation of CO2 in a freshly-fermented beer with residual gravity together with the long-term fermentable potential of that gravity, and the nomograph appears to be valid for that situation; the temperature correction allowing for the lower saturation of the existing CO2 at higher temperature.
However, it is not necessarily valid for bottle conditioning of a fully fermented dry cider where, at very best, the existing CO2 level will be at saturation only and quite probably a good bit less, and where there is no residual gravity. Under those conditions, following the nomograph will lead to less carbonation than expected. QED.
Andrew