From what I understand generally Coke is carbonated to roughly 6.2 g per liter in bottles and cans, or 3.1 volumes of CO2. I was watching this video because I was curious about how fountain soda machines worked.
By the end of the video they suggest that the soda is carbonated to around 5 volumes of carbonation. Which as I understand would be somewhere in the realm of 11 g of CO2 per liter, almost twice that of the normal soda. I imagine there are a couple other factors involved, like they are dispensing more CO2 than is actually dissolved in the soda as a consequence of trying to instantly carbonate. According to everything I know about carbonation I know from beer making they are carbonating almost 20 times higher than a forced beer carbonation technique in home brewing. Can anyone help me better understand this? I would think that the carbonation level difference between bottled and fountain soda would be something highly controlled by beverage companies for the sake of product consistency.
I did some additional reading and found that the correct maintenance levels on soda fountains with chilled water to roughly 40 degrees F is 75 psi if that helps. For 3.1 volumes of carbonation as I understand equilibrium would be just like 5 psig. I know I missing something big.
I can only assume that the rate of carbonation loss is inversely exponential as the carbonation approaches closer to equilibrium for the environmental pressure. Would 5 volumes rapidly decarbonate to 2-3 volumes but not get much lower very quickly?