Indian tonic water

Tonic water (or Indian tonic water) is a carbonated soft drink in which quinine is dissolved. Originally used as a prophylactic against malaria, tonic water usually now has a significantly lower quinine content and is consumed for its distinctive bitter flavour. It is often used in mixed drinks, particularly in gin and tonic.

The quinine was added to the drink as a prophylactic against malaria, since it was originally intended for consumption in tropical areas of South Asia and Africa, where the disease is endemic. Quinine powder was so bitter that British officials stationed in early 19th Century India and other tropical posts began mixing the powder with soda and sugar, and a basic tonic water was created. The first commercial tonic water was produced in 1858. The mixed drink gin and tonic also originated in British colonial India, when the British population would mix their medicinal quinine tonic with gin.

Since 2010, at least four tonic syrups have been released in the United States. Consumers add carbonated water to the syrup to make tonic water; this allows drinkers to vary the intensity of the flavour.

Medicinal tonic water originally contained only carbonated water and a large amount of quinine. However, most tonic water today contains a less significant amount of quinine, and is thus used mostly for its flavor. As a consequence, it is less bitter, and is also usually sweetened, often with high fructose corn syrup or sugar. Some manufacturers also produce diet (or slimline) tonic water, which may contain artificial sweeteners such as aspartame. Traditional-style tonic water with little more than quinine and carbonated water is less common, but may be preferred by those who desire the bitter flavor.

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