Why Does Bread Turn So Crispy and Tasty When Toasted?

‘Getting toasted’ means that the bread is exposed to a considerable amount of concentrated heat inside the toaster. The resultant brown color is the consequence of the Maillard reaction that occurs when bread is radiated with heat.

Bread, I am sure, is loved by almost everyone. There may be various reasons for its popularity, but for me, it’s indispensable because you can make so many delicious dishes with bread as one of the ingredients; its culinary applications are just too many to list down. But let’s talk about one of the most popular nutriments that bread offers to humankind – toast.

Why does it appear and taste the way it does?

Before you put a slice of bread in a toaster, it has its usual color, i.e. white or brown. But when it pops out of the toaster, it assumes a brownish hue. Not only that, it becomes so much more delicious than its usual self. Why does that happen?

Why does bread turn hard when toasted?

Bread attains a hardened texture after being toasted, because, well, it ‘gets toasted’. In technical terms though, ‘getting toasted’ means that it’s exposed to a considerable amount of concentrated heat inside the toaster. The resultant brown color is the consequence of the Maillard reaction (more details here) that occurs when bread is radiated with heat.

bread toasted meme 1

When you put bread in the toaster, the dry heat from the toaster eliminates every trace of moisture from within the bread. As a result, its elasticity just disappears. Poof!

This simple physical phenomenon is the reason why a toasted bread is harder than its regular self.

Why does bread’s taste change upon toasting?

So now you know why bread gets hard when it’s toasted. But why does its change color and flavor change?


Bread: Regular versus toasted

This is due to the Maillard reaction we mentioned above. In basic terms, it is a chemical reaction between reducing sugars and amino acids that gives bread its characteristic flavor. You would find applications of this reaction in a lot of day-to-day food items, including condensed milk, roasted coffee, black garlic, french fries and so on.

Bread contains proteins and carbohydrates. Due to the Maillard reaction, the outer layer of carbohydrates and amino acids combine resulting in a caramelised brown color and that signature flavor of a toasted bread. For all of this to happen, you need to heat the bread to temperatures in the range of 120 to 160 Degree Celsius (250-350 Fahrenheit), which is provided by the toaster. So you insert in a regular, relatively bland slice of bread into the toaster, and out comes a crispy, crunchy and tasty one!

While eating a toasted slice of bread, did you ever realise that such pleasant taste is actually the result of chemical reactions that occur at a microscopic level within the small particles of bread?

Now, who would have thought of that!


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About the Author:

Ashish is a Science graduate (Bachelor of Science) from Punjabi University (India). He spends a lot of time watching movies, and an awful lot more time discussing them. He likes Harry Potter and the Avengers, and obsesses over how thoroughly Science dictates every aspect of life… in this universe, at least.

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