Affordable and simple carbonation can be a fun experiment that you can easily do at home. All you really need are 2 plastic bottles with caps, a drill, white vinegar (or lemon juice), baking soda, about 3 to 4 feet of plastic tubing (the kind used for aquariums), a piece of paper or tissue, and the liquid you wish to carbonate.
First, you need to drill holes in the plastic caps of your bottles. The holes should be smaller than the diameter of your tubing and not larger; otherwise, the CO2 that is supposed to carbonate the drink will escape through those holes.
Next, cut the tips of the tubing diagonally. This cutting technique will make it easier to squeeze them into tight holes. Now, insert the tubing into the caps and securely close the bottles. Make sure that one of the tubing tips goes all the way down into one bottle, while the other tip is positioned a few inches below the cap, avoiding contact with the vinegar when added later.
Add the liquid you want to carbonate into one bottle, making sure that the tip of the tubing goes all the way down into the bottle. On another bottle, pour vinegar or lemon juice to fill 1/3 of its height. Do not close the cap just yet. Now, on a piece of paper or tissue, place approximately 3 teaspoons of baking soda and fold the tissue over it. Carefully insert the tissue with the baking soda into the bottle containing vinegar, and immediately seal it with the cap.
At this point, the baking soda and vinegar mixture will start to react. However, the reaction will not be rapid due to the presence of the paper. This step prevents the mixture from foaming over the bottle, which is not the desired outcome. Once carbon dioxide begins to form, it will move from the bottle with the baking soda and vinegar mixture into the other bottle where your liquid to be carbonated is located.
While the carbonation process is occurring, ensure that you shake the liquid bottle thoroughly. Repeat this action every few seconds to ensure proper carbonation. Additionally, for optimal results, it is advisable to use cold liquid or liquid that is nearly frozen. Continue shaking the bottle until no more carbon dioxide escapes from the tubing.
When the carbonation process is finished, here's the crucial step: ensure that you pinch the tube above your bottle of carbonated beverage before slowly opening it, just like you would with your favorite cola. Pinching the tube will prevent the fizz from escaping and avoid any mess caused by the drink spraying everywhere. Once you have safely removed the cap, you can close the bottle again using a new cap that doesn't have a hole. The other bottle containing vinegar and baking soda should be placed in a sink before you release the pinch on the tube connected to the carbonated bottle. While you are still at the sink, you can now release the pinch, and you will observe more carbon dioxide coming out, along with the vinegar or lemon juice flowing out through the tubing.
With your carbonated drink, you can either drink it right away or refrigerate it until you want to enjoy your refreshing homemade carbonated beverage!