Now with the number of wineries doubling or quadrupling, the cork industry is struggling to meet the demand _ at least with the high quality corks.
In 1997 the magazine Practical Winery & Vineyard surveyed the cork matter. The authors _ Michelle Bowen, Paul Wagner and Terry Tiff _ included these cork categories:
Grade A -very little porosity and no defects.
Grade B - more porosity and minor defects.
Grade C - moderate porosity and larger defects.
Grade D - ugly but functional.
Grade E - critical defects.
Because cork suppliers can't keep up with the demands for Grade A cork, there's no doubt that inferior quality corks are being used.
And here's the problem: As wine seeps into the more porous corks and stays there, that creates a bigger air gap inside the bottle. More air leads to quicker deterioration of the wine.
The lower grade cork with holes (from cork tree insects), channels,
cracks, and heavy porosity, contributes to the "cork taint" (TCA or trichlorolanisole) and mold spores.
The wine industry is moving to use technical corks (agglomerate,
composite cork), synthetic closures and screw caps.
Large wineries have used an aluminum thread cap with polyethylene liner for
over 50 years. This type of closure works well with some wines _ mainly sweet wines fortified with alcohol, and for wines consumed within two years or
less. Beyond that two-year time period, there's not much research.
Screw cap wines should be stored upright, not laid on their side like those with a
natural cork. Corked wines need to have the cork in contact with the wine so the cork
does not dry out.
Some wineries use metal (iron) screw caps with a polyethylene liner.
The problem with the metal screw cap is rust, which weakens the liner. This
causes the iron to come in contact with the wine, which extracts the iron back
into the wine bottle, turning the wine black.
This brings us to
the plastic closure. Synthetic closures and screw caps are recommended for
wines that will be consumed within 5 years or less.
When I make a wine, such as a cab, from the best ingredients, I'm going to use a Grade A cork.
FARINIAS CONSULTING
Ernie Farinias
8258 Andalusian Drive
Sacramento, California 95829
(H) 916-681-6241
(C) 916-768-4134
Email: ErnieFarinias@aol.com