Looking around the web, this was the closes I could find to what I am looking for, so sorry for the thread necromancy: I was thinking today: why isolate carbon dioxide from sodium bicarbonate or whatever they use industrially? Why no just use air? Nitrogen and Oxygen are at least two orders of magnitude less water soluble than carbon dioxide. It seems like a waste. I mean, I guess they would have to pump a couple hundred or so times as much gas into the liquid since its only trace in the atmosphere, but that still seems way cheaper than making pure carbon dioxide. Anyone know?
The key is to inject the carbon dioxide into the liquid and then seal it before the CO2 can come out of solution. This is only made feasible by getting the CO2 in quickly, meaning you need a small volume of highly-concentrated CO2.
Industrial scale manufacture of basic carbonated water is done by spraying atomised water into the top of a large vessel that is filled with pressurised CO2 and pumping the accumulated carbonised water out of the bottom. CO2 is pumped in to maintain the pressure as the water absorbs the gas. The large surface relative to volume of the tiny water droplets allows the CO2 to be absorbed quickly.
For carbonated drinks this is simply added to the appropriate syrup concentrate. Instant well known soft drinks. Point of sale postmix machines add the syrup at the tap, and thus have a set of syrup containers and a single large supply of carbonated water.
Seems to me I remember CO2 tanks where soda is sold.
It’s only half your fault. Changing the Y axis scaling like that is crazy. Mistakes like yours are bound to happen if you do that, and people should know better.
ETA: Oops, didn’t check the date. I guess you’re over it by now.
Yes. Sorry I was writing at cross purposes. On an industrial scale - say at a bottling plant you have big carbonation devices, mix in the syrup and then can or bottle the result.
A postmix machine has a source of carbonated water and adds the syrup at the moment of delivery of the drink. In this case the carbonation is done inside the postmix machine with an external bottle of CO2. The production rate of carbonated water is much lower, but enough to feed the machine. The critical part of a carbonator is a pump that pressurises the water supply before the CO2 is added.
Also, if you have premixed carbonated drinks (including beer) in large containers (i.e. kegs) it is usual to pressurise the system with CO2. This can be used to force the liquid through the system without the need for pumps, and also maintains full carbonation of the beverage even when the keg is almost empty.
Oh, another issue with CO2 sources. It needs to be very pure. Ordinary industrial CO2 will contain various contaminants. At much too high a level for use in a beverage. This isn’t just a health question, but many contaminants will affect the taste. So you get food grade CO2.
For pressurising beer systems you can run into trouble with pure CO2 - it will continue to dissolve in the beer and eventually result in a beer that is too carbonated. A mix, typically called “beer gas” of CO2 and Nitrogen is used to avoid this.
I thought coke was one of the few soda’s to use and have on it’s label phosphoric acid instead of carbonic acid, making it ideal for cleaning chrome bumpers and the like.
In addition to, not instead of. All carbonated drinks contain carbonic acid.
When you attach the CO2 cartridge and pressurize the bottle, much more CO2 is let into the bottle that can dissolve in the water at ambient pressure. As long a the bottle stays closed, the higher pressure forces excess CO2 into the water. Open the bottle to relieve the pressure and all the excess CO2 comes bubbling out. When the bubbling stops there is still some CO2 dissolved in the water as carbonic acid, more than there was in the water originally. This is the “acidic tang” that you mention.
Dirty secret: most industrial CO2 is food grade. I source CO2 for large-scale manufacturing as part of my job. The purity is the same. For my personal use the local AirGas store sells the same.