“Screaming” noise while steaming milk?

Question

When steaming milk (for a latte or other coffee drink), it sometimes produces a loud, high-pitched "screaming" sound. I think you can usually prevent it by keeping the tip of the steaming wand on the surface of the milk longer before putting it in deeper, but that's just a guess more than anything I've actually been taught. I've always assumed this noise means the milk is scalding, but I'm really sure.

What causes the screaming noise, and what is the best way to avoid it?

Asked by keithjgrant

Answer

The screaming noise occurs when your steaming wand can't draw in enough air. The worst that will happen is your milk will taste a little sour. Just pull the wand out of the milk for a second then put it back in.

Answered by ElendilTheTall

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