What makes sediment in wine?

Hello there! I'm Dr. Vinifera, but you can call me Vinny. Ask me your toughest wine questions, from the fine points of etiquette to the science of winemaking. And don't worry, I'm no wine snob—you can also ask me those "dumb questions" you're too embarrased to ask your wine geek friends! I hope you find my answers educational, empowering and even amusing. And don't forget to check out my most asked questions and my full archives for all my Q&A classics.
Dear Dr. Vinny,
What makes sediment in wine?
—Steve A., Federal Way, Wash.
Dear Steve,
Sediment—or “the dregs,” as some kids call it—is a byproduct of winemaking. Most of it is made up of bits of grapes and seeds, dead yeast cells, crystal-like tartrates, or molecules called polymers. Sometimes winemakers filter or “fine” a wine to remove these solids, but even after being filtered and fined, it’s not unusual for wine to have sediment.
Sediment is also a result of aging, like wrinkles and grey hair are a result of giving wine advice. As wine ages, science happens, and phenolic molecules combine to form tannin polymers that fall out in the form of sediment. That’s also what causes an aging red wine’s color to fade—those phenolic molecules include pigmentation. I typically notice these changes around the 10-year mark for wine. To separate your wine from its sediment, you can check Decanting 101.
—Dr. Vinny