Lees (fermentation)

Okay kiddo, have you ever seen how bread dough rises and becomes fluffy when you leave it out for a while? That's because there are tiny little creatures called yeast that eat the sugars in the dough and make bubbles of gas. Well, something similar happens when we make wine, but instead of using yeast, we use something called lees.

Lees are the leftover bits of dead yeast cells and bits of grape skin that are floating around in the wine after the grapes have been crushed and fermented. These bits sink to the bottom of the barrel or tank, and winemakers can choose to leave them there or stir them up and mix them back into the wine. When they choose to mix them back in, it's called "stirring the lees".

Now, stirring the lees might seem kind of gross because it's just a bunch of dead stuff floating around in the wine, but it actually has a really cool effect on the taste of the wine. When the lees get stirred up, they release some chemicals and bits of themselves into the wine that make it taste richer and creamier. It's kind of like how adding cream to your hot chocolate makes it taste smoother and more chocolatey.

So even though it might seem weird to mix dead yeast cells and grape scraps back into wine, it actually makes the wine taste better! And that's all thanks to the magical process of lees fermentation.