What Is Sediment in Wine?

What are those small dark chunks floating in the bottom of your glass of wine? Dirt? Bits of grape skins and seeds? Pieces of the cork? Unless something went horribly wrong with your wine, this is "sediment." Usually found in bottle-aged red wines, "sediment" is the pigments that gave the wine its deep, dark color when it was young. As the wine ages, those microscopic color particles clump together and settle to the bottom of the wine. They won't do anything to change the color, but they will add a grainy texture, so this is part of the reason we decant older red wines, to leave that sediment in the bottle--and out of our glass.