Why skim "scum" from the surface of a simmering stock?

Skimming scum from the surface of a simmering stock helps make it clearer and tastier.

Imagine you're making soup in a big pot, like when you’re helping Mom or Dad cook on the stove. As the water heats up and starts to bubble, sometimes stuff like little bits of fat, skin, or tiny pieces of veggies float to the top. This floating mess is called scum, it’s like the "gunk" that wants to be on top.

If you leave this scum in the pot, your soup might look cloudy and not as pretty. It can also make the soup taste a little less nice, like when you have a cookie with crumbs on it, it's still okay, but it could be better.

So, just like you would scoop out the biggest crumb from your cookie before eating it, you use a spoon to gently skim the scum off the top. This makes your soup look cleaner and taste more delicious, kind of like giving your soup a little spa day!