Carbonation

From Wikipedia, the free encyclopedia

Bubbles of carbon dioxide float to the surface of a soft drink.
Bubbles of carbon dioxide float to the surface of a soft drink.

Carbonation occurs when carbon dioxide is dissolved in water or an aqueous solution. This process yields the "fizz" to carbonated water and sparkling mineral water, the head to beer, and the cork pop and bubbles to champagne and sparkling wine. It is also behind the Mentos eruption effect.

Contents

[edit] Effervescence

Look up effervescence in Wiktionary, the free dictionary.

Effervescence is the escape of gas from an aqueous solution. The term is usually used to describe the foaming or fizzing that results from gas. In the lab a common example of effervescence is the addition of hydrochloric acid to a block of limestone. If a few pieces of marble or an antacid tablet are put in hydrochloric acid in a test tube fitted with a cork, effervescence of carbon dioxide can be witnessed.

This process is generally represented by the following reaction, where a pressurized dilute solution of carbonic acid in water releases gaseous carbon dioxide at decompression.

\mbox{H}_2\mbox{CO}_3 \longrightarrow  \mbox{H}_2\mbox{O} + \mbox{CO}_2

In simple terms, it is the result of a chemical reaction occurring in a liquid which produces a gaseous product.

[edit] Fizz

"Fizz" is a word that is used to describe the action or sound of gas bubbles moving through and escaping from a liquid. Fizz also describes the formation of a foam of this gas and liquid at the top of the liquid's container.. The word itself is an example of onomatopoeia, derived from the sound the multiple bubbles make together as they "pop" when they escape. A carbonated beverage, such as cola or beer, will form bubbles when the dissolved carbon dioxide is depressurized to form emulsions at the top, and it will make "fizzing" sounds when it is opened or poured into a container

Fizz can also result from a chemical reaction, such as a solid dissolving in a liquid to produce gas. For example, Alka-Seltzer brand tablets, used to treat stomach indigestion, form an effervescent solution that fizzes when dropped into water. When you shake the coke and you open it fizz will come out because carbon dioxide releases from the coke.

[edit] Natural and artificial carbonation

Carbonation can occur as a result of natural processes: when yeast ferments dissolved sugars sealed in a pressure-tolerant bottle or keg; when underground volcanic carbon dioxide carbonates well water; or when rainwater passes through limestone into a cave and forms a stalactite. Or it can be done artificially by dissolving carbon dioxide under pressure into the liquid. Sometimes natural carbonation is called conditioning while the term carbonation is reserved for the artificial process.

[edit] Uses

In many consumer beverages such as soft drinks (well known examples include Coca-Cola, 7 Up and Pepsi), carbonation is used to give "bite". Contrary to popular belief, the fizzy taste is caused by dilute carbonic acid inducing a slight burning sensation, and is not caused by the presence of bubbles. This can be shown by drinking a fizzy drink in a hyperbaric chamber at the same pressure as the beverage. This gives much the same taste, but the bubbles are completely absent.

Carbonation is sometimes used for reasons other than consumption, to lower the pH (raise the hydrogen ion concentration) of a water solution, for example.

[edit] Brewing

In homebrewing overcarbonation can be dangerous; it can result in bottles gushing or even exploding. Adding priming sugar or malt extract at bottling time to beer that has had its fermentable sugar content totally consumed is the safest approach to carbonation. Exceeding recommended levels of priming sugar for a given recipe is dangerous, as is using inappropriate bottles or improper capping methods. Beer may also be force-carbonated using a keg and special bottling equipment, where the carbonation level can be carefully controlled.

[edit] Carbonated beverages

A carbonated beverage.
A carbonated beverage.

Carbonated beverages are beverages which contain dissolved carbon dioxide. The process of dissolving carbon dioxide in water is called carbonation. Carbon dioxide may be naturally occurring in the beverage from fermentation or a mineral source or be artificially added.

[edit] Hazards and side effects

Carbonated liquids can pose a potential hazard; if shaken or jolted in an enclosed space such as a bottle or can, the carbonation can cause pressure to build to the point where it could cause a violent, explosive decompression when the seal is broken that could possibly cause injury. Consuming carbonated beverages can also lead to a potentially embarrassing side effect; the gasses (mainly CO2) released by the process can build to the point where they escape in a belch. It has also been shown that consuming carbonated beverages in excess during hot weather can result in dehydration and also worsen other heat-related injuries such as heat stroke.

[edit] Further reading

[edit] See also

[edit] External links

Look up carbonation in Wiktionary, the free dictionary.