Some sources suggest that home winemakers insert corks into their wine bottles dry. This is the procedure used by commercial wineries but they have corking machinery which makes it much easier to do this.
BlueStem Winery suggests (see other blog entries) that corks be soaked for approximately 30 minutes completely submerged in a sulphite solution or in a no-rinse cleansing solution prior to corking your wine bottles.
Inserting a cork dry will cause stress to the cork and may damage it enough as to no longer be an effective seal. Soaking your corks will give them more pliability which will make insertion easier and it also will help prevent bacteria growth.
Still having trouble with cork insertion? Try putting a drop of glycerine on your corking device and add another drop after approximately a dozen cork insertions. Glycerine will make both insertion and removal easier and it can be obtained both at your winemaking supply store or at a drug store. Make sure that you thoroughly clean your corking device when finished as glycerine left behind will become sticky and it will become a magnet for dust, etc. and a home for bacteria growth.
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