Homemade syrups: ratios, infusions and shelf life

Almost every sour carries syrup, and it is the easiest ingredient to upgrade. You do not need to be a cook: in its basic form it is sugar dissolved in water, and everything else is a variation on that idea.

Simple and rich: the two ratios

Simple syrup is one part sugar to one part water, measured by weight. It is the standard, and what classic recipes assume when they just say "syrup".

Rich syrup uses two parts sugar to one of water. It is denser, delivers more sweetness per millilitre and gives the drink a rounder texture. If you swap one for the other, use about two-thirds of the amount or the drink will turn cloying.

There is no need to boil. Hot tap water and a minute of stirring is enough for simple syrup; for rich, warm it a little more. Boiling only evaporates water and throws off the ratio you just measured.

Infusions: where it gets interesting

With the syrup still warm, add your aromatic and let it steep for twenty to thirty minutes before straining. Sliced ginger, cinnamon sticks, citrus peel, coffee beans, hibiscus and chilli all work well and hold up over that time.

Fresh herbs are another matter: basil, mint or rosemary need five to ten minutes at most. Beyond that they release chlorophyll and the syrup takes on a cooked-vegetable flavour you cannot remove.

How long it keeps and how to extend it

In the fridge, in a clean airtight bottle, simple syrup keeps for about a month and rich syrup for up to six. The difference is the sugar, which acts as a preservative: the higher the concentration, the harder it is for microorganisms to survive.

A splash of neutral spirit, about fifteen millilitres of vodka per half litre, extends its life considerably without showing up in the drink. And always label with the date: a syrup that has turned cloudy or has strands floating in it goes in the bin, not back in the fridge.