Cakes have 5 main Essential Ingredients* – Flour, Eggs, Sugar, a raising agent and some kind of fat, such as butter.
As a general rule, Flour and Eggs are there for structure, Sugar for sweetness, raising agent for air and Butter for flavour. To give you more of an insight into why we include each ingredient, and how they can change how your cakes, here’s a quick basic guide to Cakes Essential Ingredients. Click here for our Classic, Light Fluffy Sponge Recipe
*usually, not always. Sometimes cakes can be vegan or gluten free, so can go without one of the ingredients. This article is a generalisation for basic baking techniques
Flour, the first of Cakes Essential Ingredients, is starchy protein. It contains gluten which when stretched will strengthen and build structure. Personally, I always use a plain flour, never a self-raising **. The reason for this is you never know the exact quantities of raising agent in the flour, or how long it’s been sat there. Adding your own raising agent allows you to keep control over your recipe.
So, how does flour work? The proteins within the flour, known together as Gluten, help to build a structure when mixed with the other ingredients. This structure will help to support the cake when air bubbles are created inside
Never use strong flour, that is for bread baking. It is processed to have stronger gluten which is bad for cake baking. Also, the process of kneading in bread baking strengthens the glutens further giving that tough, ‘bready’ texture. Which if you think about it, in reverse, is the last thing you want in cake baking.
So, a plain or cake flour should be used as it has weaker gluten and lower proteins, which will contribute to a lighter crumb. Also, have you heard that you should never ‘overmix’ or ‘overwork’ your cake batter? That’s because you don’t want to strengthen or toughen the gluten, or it’ll make the mix too tough.
Most flour is from wheat, but Gluten Free Flour can be made from other grains. The problems encountered when baking with Gluten Free Flour, sometimes include a crumbly texture. That’s because the proteins needed to build structure aren’t present. Therefore, for Gluten Free baking it’s best to include something else to help with that structure such as Xanthan Gum. I would advise referring to specialist sites for more advice on this.
Too much flour in a mix can make a dry, dense cake, as it’ll soak up any liquid in the mix. Too little and your cake will fall apart as its building blocks just aren’t there to support it.
**I am a UK Baker so terms are for flours you’d find in a UK supermarket.
Eggs also contain proteins. Like flour these proteins, when cooked, will create a structure for the air to live in. The difference with egg proteins is that, because it’s liquid it can be whipped, trapping air inside it. When the cake bakes, the trapped air will expand in the heat, helping to give a light, fluffy cake.
As one of Cakes Essential Ingredients, an egg yolk is full of good fats which will add to the flavour. The better the quality of your egg, the better the taste and look of your cake. I always use free range eggs (so free range I often have to dodge the hens on the way onto the farm where I collect them), but I would advise using as good quality as you can afford. It really will affect the taste and texture of your cakes!!
One tip when using eggs is to make sure they are at room temperature. In the UK it is not recommended to store eggs in the fridge, but if you do, make sure they come back to room temperature.
The protein in cold eggs won’t whip up as well as the protein in room temperature eggs. Also, cold eggs will reduce the temperature of your cake batter which will effect backing times. And lastly, if the eggs are colder than your fat ingredient it won’t emulsify in the mix, potentially creating a curdled mix.
NOTE: Always make sure all your Cake’s Essential Ingredients are at the same temperature before your start. That way you won’t have one ingredient cooling down another and causing all sorts of chaos.
Something you may not know about sugar, is that it’s considered to be a ‘liquid’ ingredient. This is due to its ability to take on moisture, dissolve and then retain that moisture.
Sugar as one of Cakes Essential Ingredients can be a tricky one. If you add too much sugar, your mix will take on too much moisture and could become gloopy – ever baked cookies with too much sugar and they’ve ended spreading across the tray? Too much sugar means too much moisture, which means that your mix will be weakened and will collapse when baked.
However, the moisture in the sugar will help to delay the gluten development in the flour, helping to keep the cake light.
Sugar and Butter are best buddies and work really well together if you use the creaming method when baking.
If you use the creaming method – whipping your butter and sugar together before adding the rest of your ingredients – it will start to create a web of fat, sugar and air. As we learnt with the eggs, that air will expand in the heat of the oven, and will make your cake more tender.
Butter (or in some recipes oil), is a fat. Fats tend to add flavour to a recipe. Some recipes MUST have butter, but for some you can use a baking spread. Baking spreads have less fat and more water content so are fine in cakes and brownies, however the extra water content is a disaster in cookies and biscuits*** for the same reasons that too much sugar is bad in baking.
When the fat in a recipe is mixed with the flour it will shorten the gluten strands. This is done by coating the flour and impeding the gluten forming process. And, as we’ve already learnt, the weaker the gluten, the more tender the cake.
*** As I’m English, when I say biscuit, I mean classic English style ‘cookies’, such as shortbread, Bourbons and Custard Creams etc.
The 3 most common Raising Agents are Air, Baking Powder or Bicarbonate of Soda (sometimes known as Bicarb or Baking Soda – make sure you get the baking stuff and not the one to clean your drains).
Air, we’ve already covered – it expands in the ovens heat. However, sometimes a cake needs a little more help than the air we’ve managed to whip into the mix.
Baking Powder and Bicarbonate of Soda basically do the same thing, but in slightly different ways. So don’t think you can swap one for the other. Both work by a chemical reaction, which when mixed with an acidic ingredient will start to create carbon dioxide, an air in the mix.
Baking Powder often contains cream of tartare, which creates its own acidic reaction when mixed with liquid. Bicarbonate of Soda requires an acidic ingredient, such as lemon or buttermilk to create its reaction. Some recipes may require a bit of both, as Bicarbonate can create the initial burst of air, whilst Baking Powder continues the rise later in the bake.
You may think the more the better, however, don’t be tempted to overdo the raising agent. Firstly, it doesn’t taste great, so too much will flavour your cake. Secondly, if you use too much the cake will over expand, and the structure won’t be able to manage, and the cake will collapse.
Of course, these aren’t the only ingredients you use in your cake. There are flavours such as vanilla and cocoa, add ins such as fruit, nuts, and further ingredients such as coconut. But these main building blocks used in the correct quantities will make you a perfect cake.
DISCLAIMER: I am a baker NOT a scientist. This knowledge has been put together from reading baking books, watching tv and reading articles online. I not only have baked as a professional cake maker for 8 years but have baked with my Mum since I was old enough to lick the spoon, but I have no formal science education (except for secondary school, which was a loooooong time ago).