The presence of carbon dioxide in soda enables the beverage to stay fresh longer, and it acts as a very effective preservative. The very first carbonated drinks were found naturally in mineral springs around the world, and it was in the year 1772 that an English chemist Joseph Priestley discovered an effective way of mixing carbon dioxide with water and soda.
Why is Carbon Dioxide Present in Soda?
Carbon dioxide is compressed at great pressures and put into the soda bottle before it is sealed, and as such, it escapes with a loud popping noise as soon as the bottle is opened. Many people often wonder why it is present in soda or aerated drinks, and no, it is not simply to make the popping noise. It lends fizz to the recipe, improves taste, and increases overall shelf life of the beverages.
This is also the reason most beverages are packaged in glass bottles, as the glass bottles keep the carbon dioxide inside for longer. The carbon dioxide in plastic bottles of soda eventually mix with the air and get oxidized; hence, the plastic soda bottles seemingly lose their fizz faster. As a result, the shelf life of glass soda bottles is much higher.
When the compressed carbon dioxide is mixed in the bottle, it prevents the carbon dioxide that is dissolved in the beverage from escaping. Since the gas has been compressed, it is possible to mix more of it than the beverage can actually hold. Once the bottle has been opened, the dissolved carbon dioxide also starts disappearing, leading to the formation of bubbles in the beverage. After a while, the soda will simply go flat.
How to Measure Carbon Dioxide in Soda
If you are really inquisitive to find out the amount of carbon dioxide in your soda, here is a method for you. It does not require much preparation and can be easily done. Be careful not to spill the drink though, as this can drastically alter the results that you see.
All you will need is an electronic scale that can be tarred. What this kind of scale does is it measures an item and sets the weight as 0. The subsequent readings show how much mass has been gained or lost in comparison to the original weight. Also, get a few bottles of soda, preferably the 16 ounce (454 milliliters) Pepsi bottles. Now you are ready to begin your experiment.
Place an unopened bottle on the scale and tare it. Now shake the bottle vigorously without opening it. You will feel a lot of reactions happening inside. Once the froth has subsided, open the bottle slowly and let the gas or the fizz escape. Make sure that you do not spill out any of the beverage at this point. Now measure the bottle again. Repeat the process a few more times. You will find that after 5-6 readings, the mass does not change much. This means, all the fizz has escaped. The difference, you see now, is the total amount of carbon dioxide present. To confirm your observations, try it with a few more bottles.
Approximately, this amount counts up to 2.2 grams/16 ounce. To get things in perspective, this is the amount of carbon dioxide that can fill up a liter bottle at normal pressure and temperature. But you must also note that some amount of carbon dioxide has dissolved in the liquid. This will not escape into the air unless the bottle is left open for a long time.
The presence of this carbon dioxide is what lends these beverages their unique characteristics and their taste, and they have truly changed the consumer markets of the world since they emerged.