Research

Why do apples really turn brown?

When the sliced ​​apple slices are onin the air, they turn brown. How is this happening? The most common answer: due to the fact that oxygen in the air oxidizes the iron found in apples. But it is not so. Moreover, there is a way to stop this process, and even a sliced ​​apple will remain light.

One apple weighing 100 g contains about 1-2milligrams of iron - this is too little to cause such a chemical reaction. For the same reason, do not correct iron deficiency with apples, just waste your time.

Why does an apple turn brown

Apples contain many substances of the groupantioxidants called polyphenols. And when you start cutting it, the polyphenols oxidize, because when they appear on the surface of the apple slice, they begin to interact with everything that comes in their way. When the integrity of the apple is damaged, oxygen gains access to the scene and starts these processes - the apple begins to “rust”.

And why is this actually happening? The apple is thus protected from pests - for example, if the fruit has been eaten by a caterpillar. The brown “rust” that forms on the damaged surface of the apple heals the damage and protects its flesh from penetrating the damage deeper. It also makes the fruit tasteless for pests and is even capable of causing digestion in them.

According to ecologists, apples are one of the most pesticide-coated fruits. Therefore, it is recommended that you thoroughly wash the fruit before eating it.

How to keep an apple fresh

But if you cover apple slices with lemon juice,the acid that it contains will retain their original color. The acid contained in lemon juice prevents the oxidation of apple pulp in the open air - that is, those same polyphenols do not react with oxygen. This simple chemical fact is used to the full in cooking in order to preserve the attractive and appetizing appearance of apples served to the table or used to decorate desserts.

Apples are a good source of vitamin C andbeta carotene. Vitamin C is a powerful natural antioxidant. Eating foods rich in vitamin C helps to develop resistance in the body to infection pathogens and removes harmful substances that contribute to pathogens from the body.

Fresh apples are stored for several days atroom temperature. They will remain in the refrigerator for two or even three weeks. But if you decide to chop them and haven’t eaten, use lemon juice - they will definitely lie until the end of the day. The main thing is to rinse them under a stream of cold water before eating.

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