Fact Finder - Food and Drink

Fact
The Real Reason for the 'Fizz' in Soda
Category
Food and Drink
Subcategory
Everyday Foods
Country
United Kingdom
Description
Carbonated water was invented by Joseph Priestley in 1767 when he suspended a bowl of water over a beer vat at a brewery. The carbon dioxide ($CO_{2}$) from the fermenting beer dissolved into the water, creating bubbles. This discovery led to the 'everyday' soda industry. Soda stays fizzy because $CO_{2}$ is dissolved in the liquid under high pressure. According to Henry's Law, the amount of gas that can stay in a liquid is proportional to the pressure of that gas above the liquid. When you open a can, you hear a 'hiss' as the pressure drops, making the $CO_{2}$ less soluble and causing it to escape as bubbles. The 'burning' sensation of soda isn't just the bubbles; it's a chemical reaction where $CO_{2}$ reacts with water to form carbonic acid, which triggers pain receptors on the tongue.