This is the one that got the chymosin.

这是加了凝乳酶的。

The key enzyme in this mixture is called chymosin.

在这个混合物中起关键作用的酶叫凝乳酶。

And in the end, though, we thought the chymosin demo was pretty cool.

最终，我们觉得凝乳酶的实验非常厉害。

So we'll start with the chymosin samples.

所以我们将从凝乳酶样品开始。

And so what's happening here is the chymosin is swimming around in the milk, and it's binding to a protein there called casein.

在这支试管中，凝乳酶正在牛奶里畅游，它在和里面的酪蛋白结合。

An enzyme is a protein that's a catalyst, it speeds up or accelerates a chemical reaction, just as the chymosin over here is accelerating the curdling of the milk.

酶是一种蛋白，也是一种催化剂，它能加快化学反应速率，就像这里的凝乳酶能让牛奶加速凝固。

And if you were to zoom in at the molecular level and take a look at chymosin, which is the enzyme working over here, you would see it looks like this.

如果你放大到分子大小，看看处于活跃状态的凝乳酶，你会看见它的样子是这样的。