Why does the inner wall of the newly purchased kettle turn black after boiling tea?(one)

Receive messages from fans and friends. This friend said that he used the newly purchased electric kettle to make a pot of tea. The purpose is to open the kettle in this way, and the taste of metal will no longer appear in the kettle when it is used later. This friend believes that this method can effectively remove the odor in the kettle, and the tea has been soaked for a period of time after the tea is boiled and turned off. When she poured out the tea and cleaned it, she found that the inside of the kettle was severely blackened, and some rust-like spots appeared.Is it reasonable for this to happen? Why is there such a situation?

The pictures were sent by fans and friends, and the editor took a look at the pictures after receiving them. There was a judgment in my heart at that time, but in order to be cautious and rigorous, the editor did not reply to this friend immediately.Today, I will share with you the tests I did these days.

In order to confirm whether the blackening phenomenon is caused by the problem of the material, the editor found several kettles with different materials. The materials of the existing kettles in the market are usually 430 stainless steel, 201 stainless steel, and 304 stainless steel.

We set the test time to be the same, the kettle capacity is the same, the same amount of tea leaves of the same type, after boiling, let the tea stay in the kettle for 1 hour.After testing, we found that all the kettles had black inside. If the color of the 304 stainless steel inner tank is relatively lighter after being boiled, compared with the other two materials, it is relatively easy to clean with detergent later, but the color of the inner tank after cleaning is still darker than before use.

The color of 201 stainless steel and 430 stainless steel is similar, and both are darker, but the difference is that 201 stainless steel has no obvious rust-like plaques during this time. 430 stainless steel is not only black in color, but also has less obvious plaques.

Dongguan Zhanyi Commodity Technology Co., Ltd. specializes in the production of metal cups, plastic cups, coffee cups, suction mug, lunch boxes, food jar, travel mugs, portable water bottles, sports bottles, home life desktop trash cans, thermos bottles, etc.These products are all our annual exports, and are recognized and loved by the US, Europe, Australia, Japan, South Korea, Taiwan, Hong Kong and other consumers. Support for small quantity order, fast customization.