Rock Candy

Making rock candy at home is a lot of fun and even provides you with an opportunity to teach your little helpers a bit of science in the kitchen.

Basically we are dissolving more sugar into boiling water than would dissolve at room temperature. When the sugar water cools the sugar slowly solidifies back out of the solution in crystalised form. The process is called precipitation.

This technique for making rock candy is obviously not mine and there are variations of it all over the internet. The different recipes tend to vary only in the sugar to water ratio and the boiling temperature required.

Boiling the sugar solution

Here I have used a 3:1 raw sugar to water ratio (1 cup of the latter) and I merely boiled the water, slowly at first, until the sugar had dissolved fully. I didn’t try to bring it to a certain temperature and after a few minutes of a rolling boil I took it off the heat. I added food colouring and peppermint oil then simply let the mixture cool.


Crystal time

I then took a bamboo skewer and rolled it in raw sugar, the same tyoe of sugar I dissolved into the water. As the sugar crystals form over the next days and weeks, they will attach to these seed crystals.


I poored the cooled solution into a sterilised jam jar and used a bread clip to keep the skewer in place. It is important that the skewer is kept off the bottom and sides of the jar. We want the crystals to form on the skewer not on the glass. 🙂

I then put the jar in a dry, dark place until the crystals are big enough.

Note: If the crystals don’t start forming in the next few days, you can reboil the solution and add another cup of sugar. Reseed the skewer and it should then work.



The finished candy sticks

They are so amazing to look at. Almost too good to eat!

Store them in a dry place and they will last for ages. Sugar is a natural preservative after all.



I broke up the crystals in my mortar and pestle so I could use them in a Mukhwa. Mukhwa is an Indian mix of fennel and other spices, served after dinner as a breath freshener and digestive.





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