Two Homemade Tonic Water Syrup Recipes

With all this experimenting with making gin, I thought it would be fun to see if I could make tonic water to go with it, particularly as tonic water has botanical ingredients as well. Here are my learnings around making homemade tonic water syrup.

The main ingredient of tonic water is quinine. Quinine is extracted from the bark of cinchona trees, which was used as a medicine by Quechuan tribes in the South American Andes to treat shivering and fevers. They mixed the bitter powder with sweetened water to make it palatable. Jesuit priests discovered its efficacy against malaria in the 1600s and introduced it to Europe. Then over the next centuries wars were fought as some countries tried to secure their supplies of quinine and others tried to control or hide its production.

Tonic water as we know it originated as a way to provide protection against malaria for British troops in the tropics: quinine was mixed with soda and sugar to try to disguise its bitter taste. Then some inspired person realised that it tasted even better when mixed with gin!

Quinine was also used in a range of different medications but more recently some severe adverse effects of using it have been identified and it is now used much less often. I was certainly surprised to hear this as I had had no idea previously.

Besides providing the ‘medicinal’ benefits of gin & tonic, quinine is used as an important flavouring ingredient in bitters, herbal liqueurs and aperitifs, and vermouth. However because of the potential adverse effects, quinine is limited to less than roughly 100 mg⁄l in drinks.

When you are making your own tonic water syrup from cinchona bark at home you can’t determine the actual amount of quinine, but using cinchona bark pieces rather than powder, infusing it for a short period of time, and being sensible about the amount of tonic water you are consuming should limit the risk of issues.

If you search the internet, there are all manner of different recipes for tonic water. I decided to try one recipe that is essentially the basic quinine (cinchona bark*) and sugar water blend and another common recipe that adds lots of citrus and other botanicals. Both can be added to gin and served with soda water.

* Cinchona bark is a bit harder to find than the other ingredients but with a bit of searching you should be able to find a supplier online who can ship to you. During the lockdowns of 2020 it was extremely difficult to track down but this seems to have resolved now. I got mine from Cottage Hill Herbs.

Basic Tonic Water Recipe

50g cut (not powdered) cinchona bark
500ml (2 cups) cold water
1 cup caster sugar
1.5 tsp citric acid

Put the bark in a saucepan, add the water, then bring to the boil. Turn off the heat, put the lid on the pan and leave for 20 minutes.
Strain the liquid into a jug through a muslin cloth.
Add the sugar and citric acid. Stir to dissolve, then pour into a sterilised bottle.

Tonic Cordial Recipe

4 cups water
Zest and juice of an orange
Zest and juice of a lemon
Zest and juice of a lime
1 chopped stalk of lemongrass
25g (1/4 cup) cinchona bark
1/4 cup citric acid
1 tsp whole allspice berries
1/4 tsp sea salt
1 1/2 cups sugar (can replace with 3/4-1 cup agave syrup if you wish)

Combine all the ingredients (except the sugar) in a medium saucepan and bring to boil over a high heat. Once the mixture starts to boil, reduce the heat to low, cover and simmer for 20 minutes.
Remove from the heat and carefully strain out the solids using a coffee filter or muslin cloth.
Put the filtered liquid back on a gentle heat. Add sugar and stir until combined.

 

At our Gin Immersion Workshop, tutor Jill emphasised that she liked to taste her gin and thought that the tonic shouldn’t get in the way of the gin. On the other hand if you haven’t got such a flavoursome gin, you can balance it out by adding the flavours via your tonic.

I found that the basic tonic could be used quite sparingly and really brought out the flavours of a gin. I had also made a blackberry gin that was really quite sweet and the fruit overpowered the other gin flavours – mixing this with the tonic cordial balanced out the sweetness and added some much needed complexity.

Of course there is quite a trend now for pairing different gins with specific tonics, so if you are so inclined you could start to create your own tonic blends to pair with your own signature gin recipes.