Methocel A4C is one of about 20 types of Methylcellulose and is made from cellulose pulp, which is taken from plants' cell walls. It has the unusual property of gelling when it is heated and melting as it cools. Methocel A4C gels at a lower temperature than some Methylcellulose types.
One of the most dramatic uses of Methocel A4C is "instant noodles" when the diner has a squeeze bottle full of liquid that when squirted into a soup instantly turns into noodles. In addition, it is often employed as a binder in coatings, such as fried chicken batter, because Methocel A4C will solidify as soon as it hits the oil, creating a barrier that keeps the oil out and the juices in.
You can find out more about Methocel A4C from my how to use Methocel A4C guide or any of the Methocel A4C articles and recipes below.