Collapsing cell walls means the cake falls too. Quicker evaporation also has several ramifications. It makes baked goods more prone to sticking. And sugar becomes more concentrated. Some cakes won't set. Or by the time they do set, they've become dry and crumbly. Here are some guidelines for converting favorite recipes. The kids will quickly tell you that cake is airy, soft, moist, spongy and squeezy.
Bread is soft and squeezy too, but also chewy. And biscuits are solid, hard, maybe chewy, and snappy. Even though they contain the same basic set of ingredients see table above , the textures and flavours of Victoria sandwich cake, brioche bread and biscuits are completely different. Cake left is the most decadent of all with equal amounts of fat, flour, sugar and eggs, which contributes to the soft and moist texture.
Brioche bread centre , on the other hand, is more chewy and bouncy in texture thanks to the gluten that forms during kneading. The snappy structure of the biscuits right comes from the comparative deficiency of hydration in the biscuit ingredients. They are all delicious to eat, but the specific proportions and some added ingredients like baking powder and yeast make all the difference. Each contains flour, fat, sugar and eggs in different proportions see box above , which is one of the reasons for the differences in structure.
The other reason is the additional ingredients — baking powder in cake, and yeast in bread — that make the mix rise and give you that airy spongy texture. Both play the crucial role of introducing carbon dioxide into the batter or dough. Baking powder is a combination of sodium bicarbonate and a dried acid, such as cream of tartar potassium bitartrate.
But when added to the cake batter, the liquid makes it active, creating lots of tiny carbon dioxide bubbles that fill the mixture. To give maximum flexibility, commercial baking powders often have a two-stage rise — once during mixing, and again during oven baking.
The other way of introducing gases into cake batter is much more laborious. Known as the creaming method, it requires beating the butter with the sugar. You can observe this process by noticing the mixture change colour, from a buttery golden yellow hue to a creamy white, as you beat more air bubbles into the mix.
Only a few varieties are safe for human consumption, and these are mass produced for the bread and beer industries. So the important aspect for the soft fluffy baked goods is that they incorporate air before they are placed in the oven. It in this hot environment that the magic or the physics happens, and the dough or batter is transformed into a soft bread or spongy cake. During expansion, the batter or dough reaches its full volume. This is what gives us the familiar aerated texture.
Alongside this expansion, the water molecules start to evaporate and create steam, which also expands and increases the total volume of the bake. During the setting stage, the structural elements of egg and flour start to form the framework of the bake. The coiled protein molecules start to denature or unwind, and coagulate or firm up. The starch molecules absorb water and swell up until they disrupt and gelate. In the final, colouring stage, the batter shape becomes stable.
The proteins and sugars react on the surface of the bake, to create a beautifully coloured crust. Once cooked, the cake should be left in the tins for a few minutes to allow the framework to fully harden. The cake should then be turned out and left upside down to cool to room temperature.
It is the starch pectin, a polysaccharide naturally present in fruit, which enables this mixture to set into the colloidal gel that we recognise as jam. Its long chains then bind together through intermolecular interactions, and form the gel framework that then traps the sugary liquid and supports suspended fruit pieces.
Setting dramas are usually due to either a lack of pectin or too high a pH. Pectin concentrations vary between fruits. Strawberries and raspberries are low in pectin, while blackcurrants and citrus fruits have more. To overcome this, extra pectin can be added or special jam sugars containing added pectin used. For jam to set, its pH needs to be around three. Pectin chains naturally have a slight negative charge on the carboxylic acid groups meaning that they repel each other. In a slightly acidic environment, these groups are protonated and repulsion is less of an issue.
The pH can be pulled down with lemon juice, citric acid or tartaric acid and again trial and error is the key. Another key parameter is the boiling time. The mixture needs to be boiled long enough for the pectin to form, but not so long that it burns. At home, and at the Tiptree jam factory, jam is boiled at atmospheric pressure. Now all the components of your Victoria sponge are ready, the undersides of the two cakes layers should be spread with jam, and if desired cream or buttercream, before being sandwiched together.
With so much of baking having a scientific foundation, will understanding this scientific back story make you a better baker? Yes, is the universal answer from the experts.
It also helps you understand your more underwhelming offerings. Bouzari concurs. Just understanding these basic mechanisms, whether or not you use scientific jargon, is probably the number one most useful way to improve your results and your confidence and your creativity, baking or cooking savoury things at home.
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Site powered by Webvision Cloud. Now add your blueberries and stir them through the mix. Well, we know that heat is what we need to get all our superhero ingredients working together. You can open the oven door after three-quarters of the time is up, to check on your cakes, as the structure of the cake is then already created and the mix will not stretch any more.
If you really want to make your muffins look pretty, then sprinkle over some brown sugar before you pop them in the oven. How else could we make our muffins look even more yummers? I liked your info.
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