Why does the oil in the pan turn into "black charcoal"? See through the "black magic" in the oil pan

Why does black smoke appear when the oil pan is heated?

When we cook, the oil in the pan is too hot and black smoke comes out. Some careful friends may ask: Why does the oil in the pan turn black when it is heated? Is there something wrong with the quality of the oil?

In fact, the blackening of the oil pan is not a problem of oil quality, but a normal physical phenomenon.

1. The “True Face” of Oils and Fats: Long Carbon Chains

Let's first get to know fats and oils. As we know, fats and oils are composed of glycerol and fatty acids. It can be said that glycerol is like a small ball, and fatty acids are like long carbon chains. These long carbon chains are like many candles. When they encounter high temperatures at the same time, some interesting things will happen.

2. Transformation under high temperature: Oil will decompose

Oil is composed of carbon, hydrogen and oxygen. When we heat oil to a certain temperature, these long carbon chains will break and become smaller fragments. These small fragments will continue to decompose under high temperature and eventually form carbon elements. These carbon elements gather together and become the black particles we see - carbon black.

3. Oil pan and candle: a burning “competition”

Here, we may ask: Why is there not so much black smoke and carbon black when the candle burns? In fact, this is caused by the different burning conditions of the oil pan and the candle.

1. Oil pan: At the beginning, the temperature in the oil pan is very high and the oxygen is sufficient, so the oil decomposes very quickly. But as a large amount of combustion occurs, the oxygen is insufficient, and the decomposed carbon elements do not have time to burn completely, forming carbon black.

2. Candles: The burning temperature of candles is much lower than that of a large oil pan, and the amount of oxygen used is small and large. At this time, the carbon element in the candle burns more fully, and less carbon black is produced because it is almost completely burned.

3. Carbon black: a byproduct of combustion

Carbon black is a very common substance that is not only produced in oil pans (especially around the edges of pans), but also in many industrial production processes. Carbon black has a strong adsorption capacity, so it is often used to make products such as inks and tires, and of course, it is also used to make high-quality diamonds.

4. Factors affecting the production of carbon black:

In addition to temperature and oxygen supply, the type of oil also affects the amount of carbon black products. Generally speaking, under incomplete combustion conditions, oils with higher unsaturated fatty acid content (such as olive oil) are more likely to produce carbon black.

5. How to reduce carbon black?

Although carbon black is a normal physical phenomenon, too much carbon black will affect the taste and nutritional value of food, pollute the air, and is not good for health. Usually, we can reduce the production of carbon black in the following ways:

Ⅰ. Control the oil temperature: Do not overheat the oil.

Ⅱ. Increase ventilation of the cooking environment: use a range hood, etc.

Ⅲ. Choose the right oil: You can choose some oil with a higher smoke point.

Now we know that the blackening of the oil pan is a normal physical phenomenon and has little to do with the quality of the oil. Understand the combustion process of oil, master cooking skills better, reduce the generation of oil smoke when cooking, eat healthy food, maintain scientific prudence and independent thinking. In this way, it will help your life.