I problemi di tenuta della tappatura delle bottiglie di vino in relazione all'impiego del tappo in sughero

[Autom. eng. transl.] From the observations made on the basis of the experimental tests, it can be stated that, for Bordeaux bottles "neck Italy", a filling level at 20 ° C equal to about 60 mm from the top of the mouth results in the formation of an empty volume between wine and completely inadequate cork to contain the expansion of the liquid in case of storage of the bottles at temperatures near or above 40 ° C. Compliance with the appropriate filling level at a temperature of 20 ° C, which is also indicated on the bottom of the bottles and equal to 70 mm, entails, in the event of an increase in temperature, the extrusion of a part of the wine which, in our tests, is it is observed starting from a temperature of 50 ° C. At this temperature the loss of product becomes evident only in the bottle kept in a horizontal position, while in the bottle stored vertically the level of the wine does not yet reach the base of the cork. In the case of the bottle maintained vertically, the liquid begins to rise again and escapes to the mouth only after being kept for a few hours at a temperature of 60 ° C. It is shown, therefore, how, given a good regularity of the profile of the neck and a correct value of conicity of the same, the phenomenon of the extrusion of the wine with spillage to the mouth is directly linked to the thermal increase suffered by the product during the storage. The respect of the filling level foreseen at 20 ° C, for each type of bottle, allows to delay the manifestation of said phenomenon at very high temperatures for the storage of a wine and, therefore, in all probability, more difficult to reach.