What's That "Gunk" in my Wine?

[Kcwhippet]

I suspect it was probably tannin sediment. Tannins start life chemically as short chain polymers. As wine rests over time in the bottle - and yours are from 2002 - the short chains realign into long chain polymers. When they do that, they kind of surround and capture some other solid components (including any of those tartrate crystals) into their mesh and finally become so heavy they fall out of suspension. When the bottle is resting on its side (as it should be for a long period), all that gunk lines up along the side of the bottle that's on the bottom, as well as around and on the cork. Some winemakers don't fine or filter before bottling, so you can count on those wines to throw sediment after a few years of rest. David Coffaro's wines, among many others, are notorious for this trait, but we take that into account when we open the bottle.