Brown Sugar Is White Sugar With The Molasses Put Back

Brown sugar is usually not a less-processed product than white. It is generally refined sugar that has had a measured amount of molasses returned to it.

How the two are made

Cane juice is boiled, crystallised and spun to separate sugar crystals from the dark syrup around them. That syrup is molasses and the crystals become white sugar.

Soft brown sugars are then produced by blending a controlled quantity of that syrup back in, which gives a consistent colour and flavour from batch to batch.

Unrefined brown sugars exist too, made by stopping the process earlier so some molasses is never removed. These are usually drier and more granular.

Molasses brings moisture with it

Molasses is a syrup, so brown sugar carries water that white sugar does not. That moisture is why it clumps, and why it hardens when the bag is left open.

In a biscuit dough that extra water means more spread and a chewier result, since the dough is wetter before it ever reaches the oven.

It also means brown sugar measured by volume packs down and holds together, which is why recipes ask for it firmly pressed into the cup.

The acidity matters more than the colour

Molasses is mildly acidic. In a recipe containing bicarbonate of soda, that acidity is often the trigger the raising agent depends on.

Substituting white sugar in such a recipe removes the acid and the bake rises less, with a soapy edge from unreacted bicarbonate left behind.

The reverse also holds: adding brown sugar to a recipe balanced for white can produce more lift than intended and a coarser crumb.

Light and dark are a quantity, not a grade

Dark brown sugar simply contains more molasses. It tastes stronger, holds more moisture and browns faster because there is more to caramelise and more to react.

Light brown sugar is closer to white in behaviour and is the safer swap where a recipe does not name a shade.

Neither is nutritionally meaningful in the quantities used in baking, and the trace minerals in molasses are not a reason to choose one.

Storage is about humidity in both directions

Brown sugar hardens because the surface moisture evaporates and the crystals cement together. It is not spoiled and can be softened by reintroducing humidity slowly.

An airtight container does most of the work. Adding something damp, such as a slice of bread or a piece of terracotta soaked in water, restores a hardened block over a day.

White sugar has the opposite problem and clumps when it takes moisture on, which is a nuisance in a shaker but changes nothing about how it bakes.