Why is there sediments in my bottles?

[Tabby]

No need to worry about the sediment in your bottles - if anything, sediment is a sign of quality - the winemaker is anxious not to lose any of those flavours to excess filtration.. The sediment consists of small particles of the grape stalks, etc...all entirely natural. If you spot sediment in a bottle before opening, it's always best to let the bottle stand for a few hours to allow it to settle, or alternatively decant the wine. You certainly don't want to end up with a mouthful of bitter sediment!

As to the change in the taste of your wines, how much of the bottle did you originally drink? A very tiny amount shouldn't make so much difference if you re-corked straight away...maybe someone else can advise?