Muscovado, brown sugar

What may appear to be a simple baking question I find often brings about a complicated answer.  In baking if you change an ingredient it may have hidden and at times drastic consequences to the performance and the finished taste and texture of the recipe.  In the example here with my cake recipe swapping muscovado sugar for white sugar there was a noticeable difference in the texture of the cake, and I must say it really did surprise me that it was so noticeable.

I was prompted to experiment with swapping the muscovado for white sugar in my Easy Quick Light Chocolate Cakes by a question from a reader Julia who said she couldn’t find muscovado sugar and could she substitute brown sugar instead?  This made me think – what if you can’t find muscovado or brown sugar, what then?

Why do I use muscovado sugar in the first place?  Just how much of a difference does it make?  Would I notice the difference in moisture if I used only white sugar?  

What about the extra acidity in brown sugar and the consequence of having bicarbonate of soda in the recipe?

The other attribute that molasses in muscovado or brown sugar brings to the recipe is some acidity which balances out the alkaline quality of the bicarbonate of soda.  If there’s bicarbonate of soda but not enough acidity in the recipe to bring equilibrium you can end up with that soap-like aftertaste.

I baked the recipe a few times using only white sugar to find out.

Difference between muscovado and brown sugar

Here in the UK I always understood to be a clear distinction between brown sugar and muscovado sugar.  Brown sugar is white refined sugar which has the molasses (taken in the refining of it) added back in.  McGee explains two methods of doing this to the desire colour light or dark, darker containing more molasses.

Muscovado sugar comes with the sign in the pack, ‘unrefined’ and is sugar in its natural state that has been processed only to the point of its desired colour.  This less refined process makes the sugar retain more flavour as well it seems (according to some) to retain more of the cane’s natural minerals.

Sugar is hygroscopic

I use light muscovado sugar frequently when baking cakes or cookies for the extra moisture it provides.

Sugar is hygroscopic, meaning it attracts water.  I first mention this in my post Problems with Yeast Doughs.  I spent a few hours researching why sugar is hygroscopic at the molecule level but discovered no answers.  Found myself digging deep into territory that would take me days to filter through.  I bumped into this site  as you do when googling, which mentions that sugar inhibits the gelatinisation of starch, this can have dire consequences for cakes and loaves.  Again no answers as to why it delays gelatinisation of starch, it just does.

In science food books and references on the net it is an accepted fact that sugar is hygroscopic.  In baking it will take away hydration from other ingredients like flour.  For bread bakers this is particular important for gluten development if a recipe is high in sugar.

Sugars that are high in fructose are more hygroscopic.  Cane sugar (table sugar) is made up of glucose and fructose molecules.  It appears that molasses, the brown stuff in muscovado/brown sugar is high in fructose therefore making it more hygroscopic than white sugar.  Honey and syrup like molasses are also high in fructose.

I made the recipe only changing the muscovado for white sugar, everything else staying the same.

While baking I could smell a bit of the bicarbonate of soda wafting out of the oven where I couldn’t previously when baked with muscovado.  Luckily on tasting this wasn’t apparent.  I suspect the acidity in the cocoa powder provided enough balance for the bicarbonate of soda.

Different cocoa powders have different levels of acidity and some are neutralised (so not have acidity) called Dutch processed and this process seems to make the cocoa powder appear black, hence the colour of oreo cookies.

The cakes with white sugar looked the same as ones made with muscovado sugar, the only difference was a drier texture, by the next day they were not pleasant to eat.

I made the white sugar recipe again but this time with a small increase of the fat and changing the milk to cream and this improved the results, but I still felt the cakes made with the muscovado sugar were the best.

It seems if you want to change from brown to white sugar then there has to be some adjustment to the recipe.