The use of sugar in baking is vital to a baker’s knowledge, but not too complex. To understand its role in baking, we must understand where it came from. Sugar cane was the first source of white sugar. It is a grass that originated from Asia, though it now grows in many locales. It was later discovered that sugar could be obtained from beets as well. Whether cane or beet is used, the juices are extracted and purified with carbon dioxide. Sugar crystals are formed from this juice. These sugars are complex, consisting of sucrose and fructose. There are some who believe one is better than the other, but most agree they are of basically the same quality. Almost everyone knows that sugar acts as a sweetener, but it also acts as a preservative and adds volume, tenderness, and color.
When sugar is creamed with butter, air bubbles are created in the butter. The leavening agent then expands those air bubbles and the reaction creates a rise when baking. This enhances the volume of the baked goods. Sugar has hygroscopic properties, which means it also draws in moisture from the other batter ingredients. The amount of gluten is thus reduced which produces a more tender, softer end result. Less gluten also means greater volume because the baked good will raise more. Due to the fact that sugar draws in and absorbs moisture, it prolongs the shelf life of the baked good. In this way, it acts as a preservative.
Any kind of liquid sugar will hold the most moisture and stay fresh longer than if a different kind was used. Brown sugar holds the second-most moisture. This is helpful because, as a baker, I want my products to stay fresh as long as possible. Sugar also effects the color of the baked good. The browning in the oven is the result of the sugars reacting with the proteins when heated. A light-colored crust tells you there isn't very much sugar in a baked good. This is especially helpful if you are watching your sugar intake. When you understand the purpose of sugar in baking you will produce better baked goods on a more consistent basis. However, it is also important to understand the different types of sugar.
Sugar comes in a variety of colors, usually ranging from a white to a brown shade. The color is indicative of the amount of molasses manufacturers add when forming the crystals during the refining process. The size of the granules is indicative of the amount of air that is possible to incorporate. Larger granules will incorporate more air into the batter when combined with fat. However, larger granules will also take longer to dissolve. In addition, finer granules will cause more spreading in things like cookies. If you find your cookies are spreading too much, try using a sugar with a larger granule. Or try using confectioner’s sugar. The cornstarch in it deters spreading more than any other sugar.
