When choosing water for tea making, we must understand the relationship between the hardness of water and the quality of tea soup.
Natural water can be hard water and soft water.
Where there is a large amount of calcium, and magnesium ions in water known as hard water.
Water that is insoluble or contains only a small amount of calcium and magnesium ions is called soft water.
If the hardness of water is caused by the presence of calcium bicarbonate or magnesium bicarbonate, the water is called temporary hard water; If the hardness of water is caused by sulfates or chlorides containing calcium and magnesium, the water is called permanent hard water.
In other words, the taste of the water will vary with the content of calcium and magnesium salts in water. For example, high-hardness water is very difficult to drink, and even has a bitter taste, it's not suitable for making tea.
Making Tea In Hard Water
According to the hardness of water, each liter of water with calcium, and magnesium ion content of more than 8 mg is called hard water.
When there are more calcium, magnesium ions, and minerals in hard water, the solubility of tea's active components will be reduced, which will lead to the tea tasting lighter. In addition, if the iron ion content in the hard water is too high, it will cause the tea soup to turn dark brown, and even float a layer of "rust oil", and the tea soup will not be able to be drunk.
However, it is not saying that hard water is not good for making tea at all, because hard water is divided into temporary hard water and permanent hard water.
The main components of temporary hard water are calcium bicarbonate and magnesium bicarbonate. After boiling at a high temperature, it will decompose and precipitate immediately, making hard water become soft water, so it is called temporary hard water.
Most of our tea-making uses temporary hard water.
Making Tea In Soft Water
According to the current scientific analysis, water usually contains calcium and magnesium carbonate, sulfate, and chloride in the ionized state. Soft water with less than 8 mg of calcium and magnesium ions per liter of water is called soft water.
In nature, without pollution, only snow water, rainwater, and dew can be called soft water.
Soft water is widely used to brew tea soup with bright color. Secondly, because the hardness of water also affects the solubility of tea's active ingredients, most soft water makes tea with high solubility of effective components, so the tea tastes strong.
However, due to air pollution and other factors, there is very little soft water that can be collected for tea making. It is not recommended that people follow the example of the ancients to collect snow water and rainwater to make tea.
In general, it is not a common statement to choose which kind of water is the best for tea making. It is OK to choose temporary hard water and clean and pollution-free soft water for tea making.