Just wanted your opinion. What do you think it makes fondant stretchy ?
Is it :
- Gelatin
- Glucose
- Glycerin

I have a wonderful recipe from Czech site, the fondant tastes soo good, but I wish it would be more stretchy. I was able to cover a cake, but I would like to use it for modeling as well. Any suggestions???

Bump - I don't remember a lot of my college chemistry class!

Let's see, glucose is a simple sugar, so I am going to bet that it isn't what makes fondant stretchy. Glycerine is often added to soapy water when you make homemade bubbles for kids (or adults ) It makes the bubbles stretch better, so you can blow bigger bubbles. My guess is that it would add stretchiness to your fondant. The gelatin would probably also contribute to the stretchiness while also giving it some cohesiveness and structure-kind of like glue
If I were going to add something to make the recipe more stretchy, I would probably add both glycerine and gelatin but I would use a bit more of the glycerine. Then I would just play with it a bit to see what ratio works the best.
It's been a long time since I have studied chemistry, so this is my best guess.

Here's my best guess, based on what I remember from chemistry/biology class:

Gelatin can easily change state from a solid to a liquid to a semi-solid (i.e. colloid gel) depending on the amount of heat and water applied, so this ability would provide some elasticity in the molecules.
Glycerin/glycerol forms 3 hydrogen bonds when subjected to water, making it almost syrupy (i.e. viscous), so while its somewhat resistent to flow, it will still stretch to a degree. Glycerol is also hygroscopic, meaning it attracts water molecules, acting as a drying agent - its likely the most responsible party when your fondant turns hard after having been left out in the air.
Glucose is a simple sugar (monosaccharide) and is highly soluble, meaning it is either a crystal or a liquid, it does not have a semi-solid form.

So, I would venture that its probably the gelatin and the glycerin working together that provide the elasticity of fondant. Just a guess though.

Thank you so much to made me understand....I will try add both Glycerin and gelatin, and will see if it help. This fondant has great taste, but when is "resting" it became hard, they recommend to microwave and re-knead. I was able to make Rose and Carnation (the Wilton way), but because of the less stretchiness I had hard time to use the ball tool.