The butterfly (Nemapogon cloacellus) becomes 7.5 millimetres long and has a wing span of 10 to 14 millimetres. The insect likes to lay its eggs in damp places in the wine cellar. If this happens on a cork, it is eaten by the hatched caterpillar (also called cork worm) and thus leaks, which causes (besides mould) oxidation of the wine up to leakage. It is also possible that the taste of the wine is impaired by mould, bacteria and mites, which settle on the cork crumb webs interspersed with faeces and enter the bottle through the leaking cork. This can then also cause the wine to taste mouldy. You can recognize the infestation by the caterpillar itself from the cork or from corroded cork or cork crumbs or from the bottom. Uninfested bottles can be protected by covering the cork with document sealing wax. Good protection can be achieved by using Flaschen-bottle capsulescapsule. You can also combat the cork moth by using biological moth traps.
For my many years of work as an editor with a wine and culinary focus, I always like to inform myself about special questions at Wine lexicon. Spontaneous reading and following links often leads to exciting discoveries in the wide world of wine.
Dr. Christa Hanten
Fachjournalistin, Lektorin und Verkosterin, Wien