I have a picture of(from left to right) a cork from a 1978 Ridge
Zinfandel, a new cork, and a cork from a 1964 Bertani Amarone. These
wines were opened in the last few weeks. The corks were sound. However
they were very heavy. After they were allowed to completely dry in the
kitchen, they became very light and shrank so much that they will fall
through the neck of the wine bottle. The new cork was bought in about
1975. It is still elastic. The dry 1978 cork has lost all elasticity and
is hard. The 1964 cork is so hard and brittle that it is easy to break
it. The picture is at:

http://www.cwdjr.net/picsnap/WineCorks1978,new,1964.jpg

Besides the problem of corked wines, this failure of the cork structure
with extended contact with wine is the reason I hope screw caps soon
become universal. However I want a heavy duty cap that will not bend or
dent and that has a Teflon seal so that the cap can withstand minor
rough handling and can seal for many decades without problems. Of course
the present screw caps may be good enough for wines not kept for several
decades, although the weak construction of them sometimes allows the
caps to dent or bend and leak if the cap receives a blow. Surely a top,
or even average, classified wine estate could afford to pay a little
more for heavy duty screw caps, consdering the very high price their top
wines now bring.

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