Sugar is an essential ingredient in many baked goods, but not necessarily for its sweet taste. It has many unique and useful properties which make it an absolute necessity for all kinds of recipes, from croissants to sourdough bread! So how is sugar used in baking, and how does it work?

Colouring

Sugar of any kind will contribute to browning in the oven as it caramelizes. A small amount of milk or milk powder can improve crust colour in bread. Glucose and fructose brown at a lower temperature than other sugars, so ingredients like honey and corn syrup will produce a darker product than other sugars would if used in the same recipe.

Aeration

Creaming is the most effective way to guarantee a light, evenly textured product. During creaming the sharp edges of the sugar crystals cut through the fat and leave air pockets. Caster sugar has more sharp edges than granulated sugar because the crystals are finer. Icing sugar, however, is relatively ineffective for creaming because it is too fine and dissolves too quickly. The addition of chemicals or leveners such as baking powder expands the air bubbles.

Tenderness

In batter and dough sugar competes with starches and protein in flour for available water. This in turn interferes with gluten formation, tenderizing and 'shortening' the product.

Moisture Retention

Sugar in baked goods helps them retain moisture. A roll made with sugar will stay fresh longer than without. This is even more apparent with products made with sugars containing fructose (corn syrup or honey). These goods have superior keeping qualities. Cakes made from honey or molasses such as gingerbread have amazing keeping qualities, the hydroscopic (water attracting) qualities of sugar, particularly fructose is accentuated on a rainy or humid day. This is detrimental to candy making or sugar work. As the goods cool, the sugars attract moisture from the air, causing hard toffee to become sticky and gooey.

Egg, Foams and Structure

Sugar when beaten with eggs or egg whites dissolves, melting into the egg where it absorbs moisture and helps prevent weeping. This makes the whipped egg foam more stable. Sugar also raises the coagulation temperature of eggs this means the batter has more time to rise before it sets.

Spread

Sugar contributes to batter spread. It is most noticeable when cooking dough as the sugar melts it turns to liquid before setting with the other ingredients.

Fermentation

Sugar assists in yeast fermentation. Yeast will consume the sugars in a dough or batter before breaking down other ingredients. Too much sugar will have the opposite effect.