Carbon dioxide as preservative in soft drinks

Carbon dioxide acts as a preservative by preventing fermentation and inhibiting the growth of mold and bacteria. Carbon dioxide also provides soft drinks with pungent taste, acidic bite, and sparkling fizz.

Beverages are carbonated by used of a carbonator or saturator. Pressurized gas supplied to the carbonation machine is evaporated from L-CO2. Water cooled to about6 5 ° C, pumped with gas to the top of the carbonator, flows over baffles under pressure where it is saturated with carbon dioxide.

The carbonated bubbles increase the pressure in the can so that when opened, it sounds like a ‘pop’, another name given to soft drinks.

Carbon dioxide contributes to the inhibition of micro-organic growth and coupled with other factors such as pH, contributes well to the micro-stability of the drink. It acts against yeast, mold and bacteria.

It is deemed to be effective at over 2.5 or 3.0 volumes CO2 and for this reason the incidence of micro-damage in carbonated beverages is less of a problem than with the non-carbonated varieties.

The carbon dioxide used in soft drinks must be food-grade and free of impurities that may affect the taste or odor of the final product. Carbon dioxide requirements for soft drinks range from about 2.5 volumes percent of gas per volume of beverage to 4.5 volumes of gas per volume liquid for highly carbonated beverage such as ginger ale.
Carbon dioxide as preservative in soft drinks