The amount required depends on the volume being carbonates. 1L of CO2 requires about 3.5 grams of Sodium bicarbonate which is about a teaspoon. I use Potassium bicarbonate (usually used in home brewing for controlling pH) instead because 1) it works just as well and 2) it boosts the amount of Potassium rather than Sodium in my diet. As for headspace, you only leave enough that the reaction doesnt cause the contents to splatter everywhere before you can recap the bottle. The contents should be sweet enough that it doesnt matter if theres a couple grams of a Sodium or Potassium salt mixed in which isnt hard to do if you use a reasonable amount of sweetener eg. table sugar, fruit juice, stevia etc.
naevaTheRat@lemmy.dbzer0.com 11 months ago
Fair enough, I don’t drink many sweet drinks and tried to carbonate soda water that way.
Re head space, you also need to make sure you’re leaving enough when you open it. You’re only very lightly carbonating with 3.5 g. Most soda water and softdrinks have a head pressure of around 70 psi, the bottles can actually spike to around 150 when dropped which is sort of terrifying. Without the addition of all the crap they add to slow nucleation bottles can erupt very merily when opened!
When making my own soda water (I just hook bottles up to a regulated stream of co2 and shake) I do actually add some but only about 1/8 of a teaspoon per litre.
Making things slightly salty makes them nice and I find it helps reduce some of the harsh acid taste the carboxylic acid. Also it seems to modify how the bubbles form which is interesting. Maybe a surface tension of water effect? I’m unsure there.
xkforce@lemmy.world 11 months ago
Tbh I usually dont let it sit long so the fact that it isnt as carbonated is less of an issue. That said, there is also fermented soda which uses wine yeast (you can use baking yeast but this is arguably less ideal) and sugar to generate the CO2 instead of a bicarbonate base and acid. This you can essentially let sit to carbonate as much as you want but like all common ferments, it does generate a small amount of alcohol and does require dechlorination of the water you use. It also needs sugar to work while soda stream and the soda/acid method dont care how sugary the soda is.