Tonic water, soda, Seltzer: what is the difference?
Seltz, soda, and tonic water are non-alcoholic drinks which are often thought to be almost identical. This is likely due to the fact that they share an important characteristic: transparency. In reality these drinks are quite different from each other and each has its own peculiar taste, but amongst their sparkling bubbles lie unique stories and curiosities.
Tonic water, seltzer, and club soda are extremely common in the world of mixology. The merit of a successful cocktail should not be awarded only to the spirits and liqueurs that compose it, but also to the non-alcoholic elements that balance flavors, enhance aromas, and add a lively touch of something more. However, which to choose between seltzer, club soda and tonic water? Each of them has specific characteristics that make it more suitable for a specific drink than the others, starting with their distinctive tastes.
Club Soda: an effervescent English invention
Club soda, also called simply “soda”, is a carbonated water with an intense effervescence and marked savory taste. This flavor is created by adding minerals such as potassium, sodium bicarbonate, potassium sulphate, or, to make it saltier, sodium chloride, sodium phosphate and sodium citrate.
It is said that the invention of club soda dates back to around 1767 and can be attributed to Joseph Priestley, an English priest who loved philosophy and natural sciences and lived near a brewery. At that time, he began studying fermentation processes discovering that the gas released during these processes, carbon dioxide, endowed water with the bubbly characteristic found in a variety of sparkling drinks today. Priestley initially began experimenting with the drink’s healing effects, but he did not obtain the results he had hoped for.
The enjoyable taste of the drink, however, led to it become an enormous success, conquering the world as both a non-alcoholic drink and for mixing with liqueurs and spirits in prestigious cocktails. An additional advantage to club soda is that can also be used to dilute drinks and hard liquors without excessively altering their flavor, such as whiskey.
Tonic Water: a healing blend from the English colonies
The pleasantness of bubbles and the slightly bitter taste make tonic water the ideal drink to enhance the flavor profile of spirits such as gin and vodka, creating timeless cocktails. Tonic water ingredients include carbonated water, sugars, and cinchona root, the extract that lends tonic water its exclusive taste. The main difference between club soda and tonic water is that the first is composed of only water, while the second requires a recipe that creates its typical bitter flavor.
In the 18th century, the English invented this mixture of water and quinine extract as a preventive measure against malaria in the colonies of India and Africa. To counteract the bitter taste and facilitate its consumption various aromas were added. English soldiers soon began mixing tonic water with spirits such as gin. This gave life to the famous Gin Tonic, a cocktail that has endured over the centuries because of its simplicity and versatility.
The rapidly expanding market has allowed companies that produce tonic water to create sweet and “light” versions, which, with a complete absence of sugars offers a low-calorie drink. The different varieties of tonic, such as the Indian tonic and the Mediterranean tonic, are essential when mixing cocktails as their unique flavors allows them to blend with different aromas of various spirits in an alluring game of alchemy.
Seltzer: the healthy water by Schweppe
Aperitif lovers will have already heard of this effervescent water as seltzer is a fundamental ingredient for many cocktails such as the Venetian spritz and the Americano. But what is seltzer exactly? Seltzer is drinking water enriched with carbon dioxide, through a special pressurized hose. Unlike club soda, this water does not contain added minerals and its taste is neutral. It is often infused with fruit aromas and essences to create a wide range of carbonated drinks. Following the carbonation process, Seltzer water releases aldehydes, small molecules that enhance aromas and give cocktails a delightful effervescence.
The origins of this versatile mixer can be attributed to Jacob Schweppe, a German amateur chemist, who in 1792 sought to produce a drink that was healthier than soda. The word “seltz” derives from Selters, a city north of Stuttgart, Germany, where there is a source of water rich in carbon dioxide, an essential element for an excellent seltzer.