An excerpt from the link I posted above:
"Nemapogon cloacellus is found mainly in the spring and early summer. The moth grows to a length of 7.5 mm and has a wingspan of 10 to 14 mm. The cork moth lays its eggs not only on cork but also on moist wine casks in dark, dank cellars. The caterpillars of this moth species are also called cork worms.
Cork moths and cork worms are highly undesirable in wine cellars. The caterpillars destroy the corks in bottles of wine, and the wine either leaks out or tastes musty. The taste is caused by mould fungi, bacteria and mites. They settle on the cork-crumb "cocoons", which are interspersed with faeces, and thus ruin the wine."