By Harold McGee
White sugar comes in a number of different forms, which differ mainly in the size of the crystals. They go by many different names. Ordinary table sugar, used for general cooking and dissolving in drinks, is midsized. Coarser crystals are mainly used for decorating baked goods and confections, and for that reason are specially treated to produce a sparkling, crystal-clear appearance. They are made from exceptionally pure batches of sucrose, with the least possible residue of the impurities that give ordinary sugar solutions a yellowish look. They’re even washed with alcohol to remove sucrose dust on their surfaces. When a cook wants to make the whitest possible fondant, or the clearest possible syrup, it’s best to use these coarse or “sanding” sugars.