By Caitlin Mitchell CMC Tylose is super fine and won't make your fondant go grainy. Use CMC to harden fondant into a gum paste or create edible glue.
Add a small amount of powder to fondant until it feels pliable, like modelling clay to help harden it when modelling. Using CMC tylose makes fondant behave like gum paste.
Add 2 tablespoons of warm water to a quarter teaspoon of CMC powder and allow the CMC powder to melt. Don’t worry if at this stage the glue appears not to be blending. Put a lid on the container and leave it in the refrigerator overnight and in the morning you will have a perfectly clear and ready to use glue.
The glue should be a dripping consistency. If it is too thick, just add a little more water and stir with a toothpick. The edible glue should be stored in the refrigerator when not in use. To apply the glue, use a good quality paintbrush and brush on to the area where you are going to be working. Leave until it begins to dry a little so that the area is just tacky to touch.
To harden fondant into a gumpaste kneed 1 teaspoon of CMC powder into 250g of fondant. Your fondant will instantly start to firm up and will harden further when left to dry. Depending on the humidity you may need to use more or less CMC powder.
Sodium Carboxymethyl Cellulose (Viscosity rating 1500-2500 COS - fine molecular particules)