Caster sugar is another term for super fine or very fine granulated sugar.  The term caste is said to have British roots and this type is sugar dissolves easily because of the very fine granules.  Its composition is basically the same as standard or granulated sugar.  The only major difference is that caster sugar is so fine that it literally dissolves easily in water and other liquids.  Some people also refer to caster sugar as gourmet sugar because of its fine granulations.  Though not as fine and powdery as confectioner sugar, caster sugar also has very smooth and tiny granulations.

The use of caster sugar is very popular in baked treats.  From breads to cakes, superfine sugar is desired as it dissolves quite easily. This property makes the mixing of ingredients very efficient and easy.  When caster sugar is used in batters for example, the consistency will be much improved.  Any egg-based recipe like custard and mousses will have a better texture when caster sugar is used instead of standard granulated sugar.  When the latter type of sugar is used, custards may not be as smooth and soft when very fine granules of sugar are used instead.  Some people also use caster sugar to spice up cocktail drinks and other desserts.  With its very fine granules, caster sugar is a perfect sweetener to mixed drinks and other cocktails.

For people who wish to use caster sugar in one of their recipes but couldn’t find such variety in the local grocery store, processing granulated sugar may be an easy alternative.  Using a food processor, coffee grinder or blender, a person can easily convert granulated sugar to very fine caster sugar. For those who can find caster sugar available, there may be two basic varieties and these are refined and unrefined versions.  Refined caster sugar is typically white in color while unrefined versions may look yellowish.