1. Exhaust
These holes can be used for exhaust during capping. In the process of mechanical capping, if there is no small hole to exhaust air, there will be air between the bottle cap and the bottle mouth to form an air cushion, which will make the wine cap fall slowly, affecting the production speed of the mechanical assembly line. In addition, when rolling the cap (tin foil cap) and heating (thermoplastic cap), the residual air will be enclosed in the wine cap, affecting the appearance of the cap.
2. Ventilation
These small holes are also the vents of wine, which can facilitate aging. A small amount of oxygen is good for wine, and these vents are designed to help wine have access to air when it is completely sealed. This slow oxidation can not only make wine develop more complex flavor, but also extend its life.
3. Moisturizing
As we all know, in addition to light, temperature and placement, wine preservation also requires humidity. This is because the cork stopper has contractibility. If the humidity is too low, the cork stopper will become very dry and the airtightness will become poor, which may lead to a large amount of air entering the wine bottle to accelerate the oxidation of the wine, affecting the quality of the wine. The small hole on the bottle seal can keep the upper part of the cork at a certain humidity and keep its airtightness.
But not all wine plastic caps have holes:
Wine sealed with screw caps has no small holes. In order to retain the flower and fruit flavor in the wine, some wine makers will use screw caps. There is little or no air entering the bottle, which can inhibit the oxidation process of the wine. The spiral cover does not have the air permeability function like the cork, so it does not need to be perforated.