Thread by @Ri_Science

"Gin and tonic has saved more Englishmen's lives and minds than all the doctors in the empire" – why did Winston Churchill say this?

G&T was born as Europeans invaded countries across the world and were exposed to malaria – let’s explore its dark history and the chemistry behind

Gin, originally used as a herbal medicine can be traced back to Middle-ages. In the UK, gin became popular in 17th century when the Dutch/Belgian drink Jenever was introduced and adopted

Tonic took a bit longer. First, quinine and its medical benefits had to be discovered, quinine isolated and production of sparkling water invented. Tonic water was born in 19th century by mixing quinine, bubbles and sugar

Quinine’s medical effects were first observed in early 17th century Peru. Spanish colonists saw the indigenous people using the bark of the quinaquina tree to treat fever.

The bark even cured Countess of Chincon of fever - now known as malaria - when she lived in Peru

Quinaquina bark became the new gold in Europe. Europeans colonising the tropics were experiencing malaria hard and this was the first and only working defence they had

1820, French pharmacists Pelletier and Cantou isolated the active ingredient of the bark – quinine

European colonists took quinine to protect themselves against malaria, but it tasted too bitter. The British Army officers in India mixed quinine with sugar and sparkling water (& gin) to make it more palatable – G&T was born

Commercial tonic water was soon sold. The first one in 1858 by Erasmus Bond. Schweppes followed. Doesn’t the name Indian Tonic Water make sense now? It was to be drunk with or without the gin

Ever wondered what makes the combination of gin and tonic so delicious? Chemistry! Let’s get into it ⬇

Gin is a strong neutral alcohol/ethanol usually made from grains – sort of like vodka. Water is used to dilute it and juniper berries to flavour it. Ethanol draws oils out of the berries, mostly monoterpenes and sesquiterpenes giving the below flavours:

Thanks to the oil molecules in the berries, gin can be piney, woody, peppery, citrusy, spicy and mentholy. The shape of these molecules is what matters. They are very similar to quinine – main flavour of tonic. Check @sciencegeist for more info. Love this image from @compoundchem

@sciencegeist @compoundchem Quinine is a basic compound (when mixed with water, it has high pH) and so humans perceive it as bitter. Most poisons have a bitter taste and maybe that is why some people cannot stand tonic on its own. But mixing G&T creates a perfect flavour 🍸

How? The gin and tonic molecules look alike and are thus attracted to each other. This attraction creates aggregates of quinine and the gin molecules that taste completely different from just gin and tonic on their own. Info from @sciencegeist

@sciencegeist This principle of molecular chemistry makes G&T as well as other food combinations appealing to our senses. But there’s also competition between flavours and other mechanisms and molecular reactions that we do not understand that can alter our G&T experience

So for now, the perfect gin recipe relies on trial & error and tasting skills of gin makers for each new differently made batch. Once the desired flavour is achieved, only the master botanicalist knows the secret proportions of ingredients

While G&T might not be ‘saving lives and minds’ anymore, we hope you can now appreciate a glass🍸more, whether you like the taste or not 🙂

Bonus 1: always wondered why your G&T glows in bars? Read more about the physics behind this phenomenon and do a little glowing experiment at home following the instructions

blogs.ubc.ca/communicatings…

scientificamerican.com/article/shinin…

Bonus 2: ever tried tonic with a bit of salt? Why not give it a go? The change of flavour might surprise you and the chemistry behind it, too.

Does it taste sweeter? Could the salt reduce our perception of bitterness?

Have you seen pH indicating gin before? How does it work? Watch here: