Why Gin and Tonics taste amazing, according to science

We've always known that a G&T is greater than the sum of its parts, but now science has explained why.

gin and tonic limes

According to Matthew Hartings, an assistant professor of chemistry at American University and co-author of the ScienceGeist blog, we have molecular chemistry to thank for the greatness of the G&T.

It all comes down to the shape of the molecules that make up your tipple. As it happens, the essential oils that flavour gin – primarily juniper – are very similar in shape on a molecular level to quinine, the primary flavour in tonic water.

Molecules are attracted to other molecules that look like them – so, when you mix gin and tonic, molecules with similar shapes will make a beeline for each other. This is illustrated in the figure below; the blue hexagonal molecules in the gin will be attracted to their counterparts in the tonic, as will the molecules in red. 

tonic and gin science atoms molecules

Hartings explains: “The parts of these molecules that look alike are attracted to one another. When they are mixed together in a gin and tonic, the molecules come together to create an aggregate.”

As quinine and juniper molecules nestle together, the flavour they produce changes.

Hartings says: “This is why a gin and tonic doesn't taste exactly like gin plus tonic.”

This principle of molecular chemistry is behind all of our favourite food pairings – and some not-so-common ones, like oyster and kiwi or pork liver and jasmine. Both are probably amazing, but we might stick with the G&Ts for now.