This is my recipe for sugar syrup (without the sugar) which I use for the odd cocktail and for my morning coffee. Very easy to make and no blood sugar spikes.
The Inspiration
The inspiration for making it came from this great book “Better Cocktails Through Chemistry”. Written by Scott Reba, who has Type 1 Diabetes, it contains various recipes for cocktail mixers and cocktails without the sugar hit, including sugar syrup (sometimes called Simple Syrup), a mainstay of any cocktail bar.
In Scott’s case he uses Splenda which works really well. The main sweetening agent in Splenda is sucralose, a modified sugar which is hundreds of times sweeter than sugar and not recognised by the body as food so it never gets converted into blood glucose. Requiring such a small amount to give the same sweetness kick as real sugar, it also does not have the same “intestinal effects” as other modified sugar sweeteners. However, Splenda uses bulking agents so it measures the same by volume as real sugar. Those bulking agents are dextrose and maltodextrin which can spike blood sugars.
Using Pure Sucralose
While I originally used Splenda to make the sugar syrup, when it became difficult to buy in bulk from my local supermarket, I went online and found I could buy pure sucralose. This also eliminated the dextrose/maltodextrin sugar spike issue. This is the packet I bought on Amazon.

This is the 100g bag which is very roughly equivalent to 100 cups of sugar so I doubt I will be buying another for quite a while.
The history of sucralose is quite interesting in that is was discovered by accident in 1976 when a couple of chemists were exploring the properties of modified sugar molecules. When told to “test” one particular compound that had been created, the chemist thought he had been told to “taste” the compound, discovering its sweetness and thus sucralose was born.
While deemed safe by food administration bodies across the world, here is a good summary of the studies. In short there is no finding in humans to suggest there is a problem and, in terms of toxicity, you would need to consume pretty much the entire packet in one sitting to get there. Then again, eating 100 cups of sugar in one sitting probably would not do you too many favours either.
How To Make It
The standard recipe for simple syrup is a 1:1 ratio of sugar to water by volume e.g. 1 cup of sugar to 1 cup of water. For cocktails a 2:1 ratio is sometimes used. Work out how sweet for want your syrup and use the ratio that works. For sugar and Splenda the ratio is simple given Splenda measures the same as sugar by volume. For pure sucralose, without the bulking agent, things are different.
Here is what you will need to make your sugar-free sugar syrup.

Of course, we have the packet of sucralose. We also have a pump bottle for the final product and, in my case, a 1/8 teaspoon. Ideally it would be 1/16 but these can be quite tricky to find.
Why the small teaspoon? Because, as mentioned, sucralose is really, really sweet. The exact magnitude of sweetness varies in the literature so my recommendation is to see what works for you. Roughly speaking, one cup of sugar is somewhere between 1/16 teaspoon and 1/8 teaspoon of sucralose. Experiment and good luck 🙂
Once you have your 1 cup of water and (1 cup of sugar or 1 cup of Splenda or 1/16-1/8 tsp of sucralose), all you do is put them in a pot on the stove, heat the liquid until the sweetener has dissolved and you are done. Let is cool and fill your pump bottle.
For sugar, heating the water is necessary for dissolving, especially for sweeter syrup ratios but for Splenda (where the bulking agent dissolves easily) and for sucralose (where there is simply not that much to dissolve) it is less necessary. For sucralose you could probably combine in the pump bottle and agitate for the same result.
A word of warning, because sucralose powder is so fine and so sweet, it will get on your fingers and they will taste sweet for at least a few hours after making this. Also, you are welcome to try other sweeteners like stevia/erythritol mixtures but my experience is they do not dissolve well into the water, form large crystals and impart little sweetness to the syrup. A pretty result with large crystals but useless for sweetening coffee.
The End Result and Variations
Once dissolved and poured into the pump bottle you are good to go. For me, the 1/8 tsp of sucralose to 1 cup of water gave a pump of syrup which was slightly sweeter than a tsp of sugar but for coffee and cocktails it worked well enough.

Once you have mastered sugar syrup, a range of options open up thanks to the flavourings available in the shops. Using this as a base, you could add banana or strawberry flavouring for milkshakes, or create a vanilla syrup for coffee. Given the sheer volume of syrup that can be created from a 50 or 100g packet of sucralose you have a lot of opportunity to explore.