Hi Annie! That's a great question. Let's break it down step by step!
When we put vinegar into milk, we're doing a little experiment. Vinegar is a kind of acid, and milk has something called casein proteins. Normally, these proteins float around nicely in the milk.
But when we add vinegar, the acid from the vinegar makes the milk change. It tells the proteins to stick together instead of floating alone. So, they start to clump together and create little lumps. This is what we call curdling!
It’s kind of like when you play with playdough. If you smash up little pieces of playdough together, they form one big piece. That’s what’s happening with the milk proteins.
So, curdling is just the milk changing because of the vinegar! It’s like a little magic trick that helps us understand how some things work when they mix together. Pretty cool, huh?