You can't drink this kind of tea for the first time. There must be some dust in the process of making tea. These impurities will turn into bubbles after soaking in water, so you should wash off the dust first, and the water soaked for the second time can be drunk, so there will be no bubbles.
When making tea, the action of pouring water into the pot for the first time and then pouring it out is called "warm bubble". The purpose of warm soaking is to make the twisted tea slightly stretched, so as to make tea with good color and fragrance for the first time. Because of the short soaking time, the soluble matter of tea itself has not dissolved, but the tea rolled into hemispherical or spherical shape can be slowly unfolded by the momentum and heat of hot water. When the first sip of tea is brewed with water, the contact area between tea leaves and water increases. In the tea-making time of 1 minute, tea leaves can dissolve a proper amount of ingredients, making the first sip of tea have a perfect taste. Warm soaking can be said to be the first warm-up exercise for making tea, especially for double-twisted tea such as Tieguanyin. Some people say that the role of warm and moist foam is to clean warm tea, so it is not suitable for drinking.