As you probably know, baking and cooking are very different processes. Cooking is a lot more flexible, usually affording plenty of leeway when it comes to measuring and swapping ingredients. Baking, however, involves a bunch of chemical reactions that depend on the right quantities of the right compounds interacting in the right ways. So, when baking, you can't just blindly substitute one ingredient in a recipe for another. But if you want to substitute brown sugar for white sugar, you're in luck; it works, and it's simple and straightforward. However, it can change some characteristics of the finished product.
How to Make the Sugar Switch
The brown-sugar-to-white-sugar conversion is easy because the measurements remain the same. If a recipe calls for 1 tablespoon of granulated white sugar, substitute 1 tablespoon of brown sugar. If it calls for 2 cups of white sugar, substitute 2 cups of brown sugar. Even the most math-challenged of bakers should be able to handle it.
There's one caveat here, though. Granulated white sugar is a dry, freely flowing grain that naturally fills the space into which it's poured. But brown sugar has a higher moisture content that causes it to clump and sit in lumps. When measuring it, pack it down into the cup or spoon so it actually fills the entire space.
Color and Taste Changes
Brown sugar is granulated white sugar with added molasses. Different brands have varying amounts of molasses, and there's light and dark brown sugar; the former has less molasses, the latter has more. Opting for a brown sugar alternative affects the appearance and flavor of the finished product.
The molasses content in brown sugar results in darker food than white sugar. The darker the brown sugar, the more it darkens the food it goes into. It's more or less noticeable depending on what you're making. For example, the darkening stands out more in normally pale sugar cookies than in a deep brown pumpkin spice loaf.
Using brown sugar instead of white sugar won't affect the sweetness of the finished product, but it does alter the taste a bit. The darker the brown sugar, the more the molasses flavor comes through. This can impart a slightly acidic bite and a mildly bitter flavor, but it's typically not pronounced enough to detract from the quality of the food. In some cases, it enhances it, as with the warm, fall flavors of gingerbread, pumpkin, apple, chai, cinnamon, nutmeg and clove.
Shape, Consistency and Texture Changes
When you substitute brown sugar for white sugar, the most significant effects – and the hardest to predict – are usually related to certain characteristics. Don't panic – the substitution won't ruin anything. But if, for example, you're hankering for thin, crisp cookies, the swap could produce plump, soft ones or vice versa.
Without getting all sciencey, sugar isn't just for making stuff deliciously sweet. It also plays important roles in chemical reactions that occur during baking, and white sugar and brown sugar can interact with other ingredients differently. For instance, brown sugar is acidic, and white sugar is neutral. If a recipe uses baking soda, brown sugar interacts with it to produce carbon dioxide, causing baked goods to puff and soften. So, the substitution won't yield the same thin, crispy cookies you had the last time you made the recipe with white sugar.
But that doesn't mean brown sugar necessarily makes all foods softer and fluffier. It's not that simple, unfortunately. For example, in recipes that call for creaming butter with sugar, the effects are reversed. In these recipes, the loose grains of white sugar aerate the dough for softer, fluffier results. The dense, compacted consistency of brown sugar doesn't create nearly as many air pockets during creaming, giving you a denser finished product.
For just one more common example, if a recipe uses softened or melted butter, the two types of sugar have different effects on gluten development during baking. Neutral white sugar inhibits gluten formation, so dough spreads, thins and crisps more, while acidic brown sugar encourages gluten development and egg protein coagulation, so the dough sets faster, becoming thicker and chewier.
To complicate things even more, these are just examples of a single role that sugar plays, but it usually plays multiple roles in baking. So, when you trade brown sugar for white sugar, it's kind of a roll of the dice how it will alter the end product. But again, while the substitution may affect characteristics that play to personal preference, it's still safe to use; it won't render the finished product inedible.