Eli5: why do butter form from milk?


I just saw this video in YouTube making butter and I am still at awe and terribly bamboozled.

In: Chemistry

Basically making butter is refining the milk’s fats. as you squeeze out proteins and water it becomes increasingly cohesive until you get a slab of triglycerides.

Butter is made from the fats that are present in milk. When it comes out of the mammary gland, it’s a nice mix of proteins, sugars, and various necessary nutrients such as calcium and phosphorous–all the things that a baby cow/etc. needs to grow up.

You take the milk and let it settle for a while–all the cream will rise to the top. You take that cream and agitate it. This makes all of the fats stick together, and the remaining liquid, the buttermilk, comes out. You keep working the solids until most of the buttermilk is out, then you form it into a patty of butter. You take the buttermilk and make nice pancakes.