There are three gums available for making sugar gum paste. Two are natural gum products, and the other is a chemical substitute.
Gum Tragacanth – is a natural gum made from the dried sap of a plant found in the Middle East.
It has no taste but it does have a slight smell, but that disappears when mixed with other ingredients.
Gum-Tex – is made from Karaya gum which is a natural gum made from the sap of trees that grow in tropical countries such as India.
I have not used Gum-Tex myself, but I have read reports that say the smell and taste are not very good. Because it is not as strong as Tylose or Gum Tragacanth, more is required to make gum paste, and the finished product is not so white.
CMC (Carboxymethylcellulose) – is a chemical substitute which is commonly called Tylose or Tylo powder which are the trade names of CMC manufacturers.
I have used it, and It works faster than gum tragacanth but I did not think the finished paste was as good, but if you cannot get gum tragacanth, it is a good substitute.
Because Gum Tragacanth comes from the Middle East and trading conditions are not always ideal, the price of Gum Tragacanth is quite high. Because CMC is a chemical version, it is quite a bit cheaper.
I have always used natural Gum Tragacanth because I think it gives me good results and I am not keen on using chemicals in my cake decorating – at least no more than I have to.
However, they all do the same job, but, because CMC acts much faster and you can usually use the gum paste very soon after you have made it. Gumpaste made with Gum Tragacanth should be left for at least 4 hours or preferably, overnight before using it.
Making gum paste from scratch
I know some people make gum paste for flower making by adding either Gum Tragacanth or Tylose to fondant – I teaspoon to every 250g of fondant. Flowers made from this paste do not dry as hard as flowers made from real gum paste and the flowers tend to soften in humid conditions so that is why I always prefer to make my gum paste from scratch.
I always use icing/confectioner’s sugar made from sugar cane to make gum paste because I find that icing/confectioners’ sugar, made from sugar beet, does not produce such a good quality gum pastel.
Different brands of sugar tend to differ considerably and it may be the amount of cornstarch the manufacturer has added to keep their product flowing.
Recipes on my blog
In the recipes, I have put on my blog, I have said to use 3 teaspoons of Gum Tragacanth but I find that with some brands of sugar I need only use 2 teaspoons because 3 makes it too stiff to work with.
The first time you make gum paste you will know what quantity of gum your brand of sugar will need. If your first batch is too stiff, then cheat and add a little bit of fondant to it so that it is easier to use and you don’t waste it.