I'd like to point out a common misconception related to the
Champagne cork. As incorrectly mentioned in the otherwise excellent writeup about the wine, the cork is
not mushroom-shaped prior to closure.
The
Champagne cork is originally
cylindrical but differs from other corks being longer and considerably wider in diameter. More
compression is used to insert the cork about 44mm into the bottle, leaving an exposed portion above the neck of bottle for the
cage to grip. The
conical nature of the inside of the
Champagne bottle will result in the lower portion of the cork deforming into a
conical shape as the pressure of the wine inside attempts to force it out of the bottle while it is retained from doing so by the wire
cage. In my personal experience with
sparkling wine, pressure
gauges inserted into a random sample of the bottles undergoing second fermentation, the pressure reaches a peak of 6
bar (about 80
psi) prior to
degorgement, enough to deform a cork over an extended period of time
On a final note, recent
trends have favoured a
twin-top cork, one where the body of the cork utilises
agglomerate cork with two discs of natural cork at the top and bottom.
Agglomerate cork withstands more
pressure while the
natural cork in contact with the wine absorbs liquid and expands, improving the
seal with the bottle
wall.