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I am curious about why those who invented carbonated drinks chose to use specifically carbon dioxide in the liquid, instead of some other gas (say, oxygen).

(Obviously they wouldn't necessarily have been called "carbonated" if some other gas had been used, but that is besides the point.)

Is there some reason such as that CO2 does not dissipate from a liquid as fast as other gases, or something else?

  • cherry phosphate anyone? – Pat Sommer Jan 3 '15 at 3:22
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    I remember there being a story in Japan of hydrogenated beer allowing people to sing higher notes at Karaoke bars and igniting burps with lit cigarettes(!) Don't remember where I read it. Have to look around... – user31483 Jan 5 '15 at 1:29
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    Oxygen was too lonely by itself so it had to get his buddy carbon to join the bubbly fun and now you got CO2 instead of just O – Huangism Jan 5 '15 at 15:34
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    @JosephMurray that will be darwinawards.com/legends/legends1999-11.html – Dawood says reinstate Monica Jan 6 '15 at 23:39
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    @DavidWallace - while amusing, that story is an urban legend – Johnny Jan 7 '15 at 0:32
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CO2 tastes good! Carbonated water is actually a weak carbonic acid solution; this is what you taste. It's like "salt and pepper", but for water.

Slightly acidic water is usually popular, hence lemon juice is sometimes used to taint a jug of water in times when no carbonated water is available.

Carbonated water releases CO2 bubbles for many minutes after pressure is released (dissolved carbonic acid reforming), which is an important presentation effect that other gases do not generally have.

In many countries the local water supply is slightly alkaline (due to limestone rock being very common), and this can leave a bad after-taste, and make food in your mouth taste soapy. The addition of weak acids to water helps with neutralising this effect.

Around the world, some lucky towns have natural springs with effervescent water (carbonated water), and man-made carbonated water is just imitating this. In history people have often travelled great distances to try effervescent water, so its popularity is well recorded.

Nitrogen is used for water pressurisation in brewing and cooking as it leaves little or no taste, and generally does not form other chemical compounds. It's used mainly when bubbles are required, but not an acidic taste.

Oxygen is unsuitable for water pressurisation as very little can be dissolved at normal soda pressures, and it has no taste, but may readily form unwanted chemical compounds.

In the 18th century, Joseph Priestley was the first person to document this manufacturing discovery. He noted precisely that it tasted good, and that it was similar to the German Selters water. He was discovering "airs" (gases), and uniquely identified quite a few different gases. CO2 was the only one he listed as tasting good. His cheap source of CO2 was the fermenting grains from the nearby brewery.

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    Also, oxygen is quite a bit more dangerous to handle (probably not the main reason it is not used, but just in case someone wanted to try...) – nico Jan 3 '15 at 11:23
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    Actually, most of the "taste" of carbonated water is the carbon dioxide setting off the pain receptors in your mouth. (Yay, masochism!) – David Richerby Jan 3 '15 at 12:52
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    O2 would also be a lot more expensive. – jeremyjjbrown Jan 3 '15 at 19:58
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    Why has this answer been accepted? It may be full of interesting facts but the question was "Why did people start using CO2 in drinks", and the correct answer (given below by David Powers) is that it was a by-product of fermentation. Before anyone says carbonated = non-alcoholic, ginger beer. – Peter Wone Jan 5 '15 at 0:03
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    @PeterWone: David's answer is also incorrect in the sense you say this answer is incorrect - the answer is that it's because naturally bubbly mineral water are carbonated and people imitated what nature produced (as stated in this answer). A more complete answer is probably both. It's like saying Diamler invented cars while ignoring Benz. – slebetman Jan 5 '15 at 4:08
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Brewing processes often introduce carbon dioxide naturally, usually along with alcohol.

Carbonated beverages get the fizz and some spiciness/acidity without the alcohol.

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    I think this is the real answer. Slightly fermented drinks were popular before industrial carbonation. Taste is not the reason why people started using CO2, but why they continued it. And it is an acquired taste. But many already had acquired it before there were chemically carbonated sodas. – rumtscho Jan 5 '15 at 9:06
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Oxygen is MUCH less soluble in water than carbon dioxide. This is due to formation of carbonic acid. There would certainly be much less "fizz" if soda was charged with oxygen under the same conditions of pressure and temperature.

Also it might be undesirable to have high oxygen concentration in the sealed drink as this might reduce shelf life. In certain ways carbon dioxide can act as a preservative.

All answers posted so far sound good.

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    Bottles pumped full of oxygen would also be a major fire hazard. – David Richerby Jan 3 '15 at 12:42
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    @DavidRicherby Drunks would no doubt have great fun dropping lit cigarettes into such bottles. Instant fireworks! – Wayfaring Stranger Jan 3 '15 at 16:21
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    Water normally has dissolved oxygen. Adding more (still less than 1%, as in carbonation) isn't going to make any difference – TFD Jan 3 '15 at 20:54
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    @DavidRicherby It's not that simple. Read up on Henry's Law re. dissolved gasses. Also, CO2 does not just dissolve, it forms a chemical compound (carbonic acid), hence you can get grams per litre, with oxygen you are only ever going to get mg per litre – TFD Jan 4 '15 at 1:42
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    @Mehrdad Because it makes fires burn more vigorously and, in high enough concentration, it can make things spontaneously combust. – David Richerby Jan 7 '15 at 8:32
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An interesting addition to the answers above: There's such thing as nitrogenation, where nitrogen is used along with CO2. This is done mostly to replicate the flavor of beer with less carbonation, which is common in places such as England where beer is served at 55F. CO2 becomes less able to dissolve with temperature increase, therefore higher temperatures mean less carbonation. Many beer drinkers say that carbonation makes flavors harsher, whereas nitrogenation replicates "traditional" beers where the carbonation affects the taste less. It also has effects on mouth feel and appearance.

A nitro beer will taste a bit flatter, but will make up for that with a full, creamy mouthfeel.

source: Beer On Nitro - A Brewer's Explanation

CO2 isn't the only thing used to add effervescence to beverages. It's just the most common.

  • As anyone who's ever drunk Beer or any other draft drink fro ma English pub will tell you; There is no standard serving temperature, in fact it's highly likely that some places go out of their way to warm the stuff up!!! ;-) – Phill Healey Nov 17 '17 at 12:30
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To be a little more historical (why people started using CO2), I'll say that bubbly beverages all originated from fermentation. Even things that we have as non-alcoholic beverages - root beer, ginger beer, used to be fermented a bit (and still are, by people that make their own.)

The flavors that we have come to enjoy were developed in the context carbonic acid, especially the sweetness. And as others have pointed out, oxygen is bad for flavors. Beer in particular is affected by oxygen, the yeast will generate sour/cidery flavors in the presence of oxygen and other stale flavors appear.

Side note: artificial addition of nitrogen to beer is a recent thing meant to mimic traditional cask ale, where carbonation is low and air is forced into the cask to push the beer out. In the short time before the oxygen damages the beer, the nitrogen will dissolve in the beer giving smaller bubbles and creamier foam.

  • Natural soda springs occur all around the worlds. Surely people would have drank those long before bottled fermentation was achieved – TFD Jan 3 '15 at 20:48
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    True, and I have tasted some of that water direct from the source. It often contains SO2 or H2S, yet that has not caught on yet (luckily). – Pepi Jan 4 '15 at 4:53
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Man tends to follow nature.

Water passing through limestone ( CaCO3 ) dissolves a tiny amount of the limestone and flavors the water.

If that water is artesian, it can have more dissolved Limestone, but as the water exits the ground, into a condition of lower pressure, the dissolved CO2 is released ( forms bubbles ).

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None of these answers is actually quite right (though some come close). First, it has nothing to do with simulating natural fermentation products or naturally occurring liquids. Nor does it have anything to do with safety in transport. Nor does it have much to do with taste (especially since, as others have already pointed out, the sensation of soda has very little to do with taste, and much more to do with stimulating nociceptors in the mouth). CO2 is used because it is one of the only non-toxic, easily and cheaply producible gases that can remain dissolved in significant concentrations in water. while about 1.75g of CO2 can be dissolved in a kilogram of water at room temperature, only about 0.02g of nitrogen can dissolve in the same amount of water. The situation is not significantly better for oxygen, where only about 0.04g per kilogram of water will stay in solution.

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    There was actually one older answer (cooking.stackexchange.com/a/52218/1672) that does mention solubility, but your answer (especially the numbers, showing the two order of magnitude difference) is really helpful too. – Cascabel Apr 11 '17 at 4:04
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I would think the Oxygen would chemically interact with the sugars and other components of the soda, and in effect burn the contents!

  • Water normally has dissolved oxygen. Adding more (still less than 1%, as in carbonation) isn't going to make any difference – TFD Jan 3 '15 at 20:49
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    @TFD The amount of gas dissolved in tap water is of the order of milligrams per litre, which is negligible; the amount of gas dissolved in soda is of the order of grams per litre, a hundred to a thousand times more. That's going to make a difference. – David Richerby Jan 3 '15 at 23:12
  • So do we know for sure if oxygenating drinks would create undesired chemical reactions? – user1306322 Jan 6 '15 at 1:39
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Adding my 2 cents: Having constructed a coke bottling plant (not operated), I'm aware that tiny amounts of activate carbon is an ingredient and the reason given was that it would react with any dissolved oxygen thereby inhibiting bacterial growth in the sugared drink.

In fact, if you were to drink fresh coke from a bottling plant, it's a bit harsh on taste. This, I'm assuming here; is because the activated C in the drink initially forms concentrates of CO3 ions before it squeezes out the remaining O ions from the solvent to stabilize to dissolved and evenly spread CO2. I must admit, that I couldn't balance the equation here.

But I do know that if you mix coke with say a bacterial fermenting item like say yogurt or beer; cap it and rock it; it could result in a small and sudden explosion. The trick to bottling coke lays in carbonating it before any bacterial formation could take place.

  • What bacteria grows in a liquid that is as acidic as vinegar? – rackandboneman Nov 18 '15 at 22:35

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