Baking cookies is astounding. You put little balls of wet, white dough into the oven and out pop brown, crispy, tasty biscuits. So, what do you think is going on in that oven? Let’s now look at the three major steps of the cookie-baking process.
1. The spread: Did you know that when the cookie dough starts to heat up, the butter in it melts, so the ball of dough loses its structure and spreads out.
2. The rise: At 212 degrees Fahrenheit, the water in the dough turns into steam. This, in turn, causes the cookies to rise as the vapour pushes through the dough. Ultimately, the baking powder/soda starts to break down into carbon dioxide, which makes the cookie rise further. Did you know how cookies become light and flaky? It is due to these gases which leave little holes in the cookie.
3. Colour and flavour injection: This is caused by two chemical reactions. Initially, caramelization takes place. As the sugar in the dough breaks down, they are transformed into a brown, fragrant liquid that overflows with aromas and tastes. Secondly, it’s the Maillard reaction. This involves the sugar in the dough, as well as, the proteins from egg and flour. It brings out, toasty, nutty and even savoury flavours. This reaction also darkens the cookie’s surface.
Another interesting fact is that the diameter of the cookie depends on how quickly the dough spreads out as the butter melts in the oven. For instance, if you use melted butter, then it would result in a much flatter cookie.
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