Cake faults, finishing and storing

25 min

Let's begin

Every baker has opened the oven to find a cake sunk in the middle or split open on top. A fault is not a disaster: it is information. The shape and texture of a failed cake show what went wrong, whether it was the oven, the measuring or the mixing, so that the next one comes out right. This lesson shows how to read and correct common faults, how to finish a cake with icing and simple decoration, and how to cut, store and serve it safely.

Definition

Cake fault: a problem in a baked cake's shape, texture, colour or taste, caused by the ingredients, the method or the baking.

Texture: the structure of the inside of the cake, the crumb: fine and even, coarse with large holes, or close and heavy.

Icing (or frosting): a sweet coating for a cake. Glacé icing is icing sugar mixed with a little water or lemon juice; butter icing is soft butter beaten with icing sugar.

Common faults

Fault	Likely causes	How to prevent it
Sunk in the middle	too much raising agent, sugar or liquid; oven door opened early; oven too cool; cake under-baked	measure accurately with level spoons; keep the door shut for the first two-thirds of the time; test before taking it out
Peaked and cracked top	oven too hot, or tin on too high a shelf; tin too small; too much flour or too little liquid	check the oven temperature and use the middle shelf; use the right tin; mix to the right consistency
Close, heavy texture	too little raising agent; fat and sugar not creamed enough; mixture curdled; oven too cool	cream until pale and fluffy; add eggs gradually; preheat the oven
Large holes (tunnels)	flour beaten in instead of folded; raising agent not mixed in evenly; air pockets left in the tin	sift the flour and raising agent together; fold gently; tap the filled tin
Fruit sunk to the bottom	mixture too soft; fruit wet or sticky; too much raising agent	dry the fruit and toss it in a little of the flour; mix to a stiffer consistency
Burnt outside, raw inside	oven too hot; tin too deep or too small	lower the temperature and bake for longer; cover the top with paper if it browns too fast
Dry and crumbly	over-baked; too little fat or liquid; too much flour	weigh accurately; test a few minutes before the stated time

CAKEMEAWAY: a baker explains the common reasons why a cake sinks in the middle. Match each reason in the video to a row of the faults table in this lesson.

Finishing a cake

Finish	Recipe	Best for
Glacé icing	200 g icing sugar with 2–3 tablespoons of water or lemon juice, added a little at a time until it coats the back of a spoon	tops of loaves and small cakes; it sets firm and shiny
Butter icing	soft butter and icing sugar in the ratio 1 : 2 by mass, beaten with 1–2 tablespoons of milk; for chocolate, replace a quarter of the icing sugar with cocoa	filling and covering sponges and chocolate cakes
Cream-cheese frosting	soft butter beaten with icing sugar, then cold cream cheese beaten in briefly	carrot cake; must be kept in the fridge
Simple decoration	icing sugar sieved over a paper stencil; grated chocolate; lemon zest; fresh fruit; piped stars of butter icing	any cake

Always ice a cake when it is completely cold: on a warm cake, icing melts and slides off. Brush loose crumbs off first, and spread a thin first layer of butter icing (a crumb coat) to hold the crumbs before the final layer.

Storing and serving

Cool the cake completely, then store it in an airtight tin or box. Plain sponges keep 2 to 3 days; rich fruit cakes keep for weeks.
Cakes with fresh cream or cream cheese go in the fridge and should be eaten within 2 to 3 days.
Un-iced cakes can be wrapped tightly, labelled and frozen.
Display cakes covered, cut them with a clean knife dipped in hot water and wiped, and serve slices with a cake slice or tongs, not fingers.

Worked example

Worked example 1: butter icing for a layer cake. To fill and cover the chocolate cake, a baker plans to use 150 g of butter. How much icing sugar and cocoa does she need?

Butter : icing sugar = 1 : 2, so the "sweet" part is $2 \times 150 = 300$ g.
For chocolate icing, a quarter of it is cocoa: $\frac{1}{4} \times 300 = 75$ g of cocoa and $300 - 75 = 225$ g of icing sugar.
Beat with 1–2 tablespoons of milk until smooth and spreadable.

Worked example

Worked example 2: cutting 12 equal slices. A round cake is 20 cm across. What angle does each slice make at the centre, and how wide is each slice at the edge?

Angle: $\frac{360^\circ}{12} = 30^\circ$ .
Width at the edge (arc length): $\frac{\pi \times 20}{12} \approx 5.2\,\mathrm{cm}$
Mark the cake in half, then each half into six, cutting from the centre outwards.

Warning

Food safety for cakes. Do not taste raw batter or lick spoons: raw eggs and raw flour can carry harmful bacteria. Keep cream and cream-cheese cakes cold. Tie back hair, wash hands before decorating, and never sell or serve a cake with mould on it; cut a mouldy cake out completely, do not scrape the mould off.

Tip

Memory hook: "Sunk? Too much, too soon or too cool. Cracked? Too hot or too small."

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Practice

Give two causes of a cake sinking in the middle.
A cake has a high peak with a crack across it. What two faults in baking are most likely?
How can you stop dried fruit sinking to the bottom of a fruit cake?
Why must a cake be completely cold before it is iced?
How much icing sugar is needed with 120 g of butter for plain butter icing?
A 24 cm round cake is cut into 16 equal slices. Find the angle at the centre and the width of each slice at the edge.
A student's sponge was heavy and close, and she says "the recipe is bad". Analyse the likely causes from her notes: "used butter straight from the fridge; added the eggs together; put the cake in when the oven was switched on", and advise her.

Show answersHide answers

Too much raising agent, sugar or liquid; the oven door opened too early; the oven too cool; the cake under-baked (any two).
The oven was too hot (or the tin on too high a shelf), and/or the tin was too small, so the outside set before the middle finished rising.
Dry the fruit well, toss it in a little of the recipe's flour, and mix the batter to a stiffer consistency.
Icing melts and slides off a warm cake, and the cake may break or become soggy.
$2 \times 120 = 240$ g.
$\frac{360^\circ}{16} = 22.5^\circ$ ; $\frac{\pi \times 24}{16} \approx 4.7$ cm.
Cold butter does not cream, so little air was trapped; adding all the eggs at once probably curdled the mixture; and a cold oven let the gas escape before the cake set. The recipe is not the problem. Use soft butter, cream until pale and fluffy, add the egg gradually, and preheat the oven for 15–20 minutes before baking.

1Common faults

2Finishing a cake

3Storing and serving

Common faults

Finishing a cake

Storing and serving