Most drink recipes that include simple syrup refer to one-to-one (1:1) simple syrup: equal volumes of sugar and water. However, some bars use a sugar-heavy two-to-one (2:1) simple syrup, sometimes called “rich simple syrup.” It’s a good idea to ask a bartender which ratio they use if you’re asking them for a recipe.
Simple Simple Syrup
To make 1:1 simple syrup, you don’t need to heat the water, contrary to popular opinion. Just add equal volumes sugar and water (a cup of each, for example) to a bottle and shake it up until the sugar dissolves completely. Store it in the refrigerator between uses and it should last about a month.
Interestingly, when you heat syrup it becomes less viscous. Professional syrup maker Jennifer Colliau explains, “Sucrose is comprised of a fructose molecule and a glucose molecule bonded together. When you heat it with water, you begin the inversion process whereby the bonds are broken, and you end up with glucose-fructose syrup, also known as invert syrup. It takes a while to fully invert it, but heating it at all makes it partially invert. Sucrose is more viscous than either glucose or fructose. So cold-dissolved simple is more viscous.”
Viscosity, in most cocktails, is considered a good thing; it gives drinks a nice silky texture. But at the end of the day, I don’t heat my simple syrup because it’s easier not to.
Spoilage Time of Simple Syrup
One-to-one simple syrup spoils after about a month- you’ll see a cloudiness forming at that stage, which will later become mold. On Alcademics, my other cocktail blog, I conducted an experiment to see how long it took for simple syrup to spoil. I made 1:1 and 2:1 syrups, plus each of these syrups with the addition of a tablespoon of vodka. (The vodka helps prevent spoilage and doesn’t add flavor to your drinks. However if you also use simple syrup for your morning coffee then the vodka might not be such a good idea.)
I found that 1:1 simple syrup spoiled in about one month, 1:1 syrup with vodka lasted three months, 2:1 simple syrup went six months without spoiling, and 2:1 simple syrup plus vodka was still unspoiled when I stopped the experiment at six months.
Should you decide to make rich simple syrup (you’ll probably have to heat it to get all the sugar to dissolve) keep in mind that it is denser with sugar than 1:1 syrup. In other words, don’t just half the quantity of 1:1 syrup called for in a recipe; use less than that and see how you like it. You can always add more syrup, but you can’t take it out.