Yes that’s right you can make sugar-free royal icing!
This recipe works just by replacing icing sugar with powdered xylitol or SukrinMelis.
For information about sugar-free celebration cakes or sweeteners, please visit Sugar-free celebration cakes.
I recommend using pasteurised egg white for this recipe.
Use the royal icing straight after mixing. It will pipe as well as usual royal icing but it will take longer to set and will not set as hard. It will crust over but will be quite soft underneath. It is quite fragile.
For a fondant icing recipe, see here.
2 x 5g sachets free range egg white powder
4 tablespoons cooled, boiled water
330g powdered xylitol or erythritol
Place the egg white powder into a large mixer bowl with 2 tablespoons cooled, boiled water and whisk together. Add the remaining 2 tablespoons water and whisk to dissolve the powdered egg white.
Sieve the powdered xylitol into a bowl and mix into the egg white ensuring not to leave any powdered sugar on the sides of the bowl.
Beat together until the icing forms thick peaks. When you lift the beater, the icing should stay stiff. Place a wet clean tea towel over the bowl to prevent the icing drying. Use as needed.
If the powdered xylitol is quite grainy, it may not push through certain piping nozzles. You could try passing it through a clean, unused nylon stocking into your piping bag.