The skill of Italian machine milk foam

① uses a special steel cup, the top is narrow and the bottom is wide, it is easy to form a whirlpool, pour in full-fat fresh milk until it is full. ② first put steam to drain water, then let the steam nozzle form a 45-degree angle with the surface of the milk, and insert the steam pipe into the fresh milk about 1CM. Open the steam valve and start heating, making the fresh milk whirlpool, so that the steam and fresh milk are fully mixed to produce milk bubbles. ③ when the milk foam reaches nine minutes full, close the steam valve and scrape off the thicker foam with a spoon.