Why do cakes split on top?

 

It’s quite normal for most cakes to rise slightly, but if a cake ‘domes’ in the centre and/or cracks significantly (a little cracking we can all live with), it could be due to one or a combination of the following reasons:

• The temperature in the oven is too high. If the top crust develops and solidifies before the cake has completed rising, the center will attempt to push through the crust as it bakes, causing the cake to crack and perhaps dome. If your oven is becoming too hot, use an oven thermometer to adjust the temperature. If the temperature is reading as correct or the problem persists, try reducing the temperature by 10°C and see if this helps – the temperature given in a recipe may be incorrect. Additionally, always bake cakes on the middle shelf (or whatever indicates the cake is in the center of the oven); if the cake is cooked on the top shelf, the heat may be too strong.

• The batter includes an excessive amount of rising agent. Too much baking powder will cause a cake to rise too quickly and too much, making it crack or spill over the sides of the tin. Reduce the quantity of raising agent used, or use a blend of plain and self-raising flours, to get a more equal surface.

• The tin is insufficient for the quantity of batter. If this is the case, there is obviously nowhere other than up for the cake to go as it bakes, and it will inevitably dome and then crack. This is readily remedied by using a bigger tin.

• There is an imbalance in the recipe. Too much flour or too little liquid such as milk or eggs, for example, will cause the batter to be thick and less ‘flexible’, and result in cracking on the surface as the cake bakes, as well as a heavy, dense texture. Trying to fix an ingredient imbalance in a recipe can cause more problems than it solves, so the best solution for a ‘bad’ recipe is simply to try a new one from a trusted source.

• The batter has been overworked. Overmixing will cause the gluten to form, making the batter heavy. The end result will be akin to having an imbalance of components. To avoid this problem, take note of the instructions in the recipe and only beat or mix for as long as it states.