Methylcellulose

Cellulose gums, of which there are several, have an unusual characteristic: They set when hot and turn liquid when cold. They are sometimes used in baked goods, such as pies, to prevent hot liquid released by fruit from running out the sides. Once the pie cools, the firm fruit gel formed by the cellulose returns to a liquid. This strange characteristic of turning liquid when cold has led chefs to invent any number of (sometimes bizarre) dishes.

Methylcellulose (E)

is the cellulose gum most important to the saucier. When combined with xanthan gum and piped through a whipping siphon, it yields a foam much like meringue or royal icing with air in it. When the mixture is hot, it is used to make hot marshmallows. The methylcellulose and xanthan gum are dissolved in cool to slightly warm water. The water is heated until the gel sets and the gel then chilled until it returns to liquid form.