Everything you need to know about the bubbler cap. Quick guide to craft wine and beer production

The bubbler cap, although its technical name indicates it, is not a real cap designed for the conditioning of wine and / or craft beer, but rather a kind of valve allowing the partial or total elimination of carbon dioxide produced by fermentation. Very different from beer and wine crown cap, generally used for the preservation of sparkling liquids, the bubbler cap prevents the entry of oxygen by promoting so-called anaerobic fermentation, that is to say carried out in the absence of oxygen.

As a rule, in beer production, the elimination of carbon dioxide is partial, while in that of wine, it is almost always total.

Bubbler cap: when to use it

This type of stopper, which actually looks more like a valve, is mainly used in craft production, or by those who make beer (or wine) themselves at home, but also by micro-breweries and micro – wine production.

In principle, because of the much higher volumes, in industrial production, much more sophisticated and technological systems, using a series valves and any other type of equipment, are used for the elimination of carbon dioxide and the carrying out of the anaerobic fermentation process.

The instrumentation certainly changes, but not the process. The partial or total elimination of carbon dioxide is a phase generally required in any type of beer or wine production.

How the bubbler cap works

But how does the bubbler cap work in practice? This special valve uses a coil, which can be glass or plastic, half filled with water. The coil is always placed above the cap and communicates with it, so that the gas can accumulate in bubbles and rise as water.

It is precisely because the gases remain trapped in the bubbles that they are isolated from the fermented drink and, thanks to the pressure of the water, they can rise and be expelled by bubbling, hence the name of the cap.

External oxygen, on the other hand, always thanks to the pressure of the water, cannot penetrate into the container of the fermented drink and thus promotes anaerobic fermentation. The system is actually very simple and is made possible by the basic laws of physics, which is why it is widely used in small craft productions. For industrial production, given the volume of fermented wine, it is necessary to use another type of instrumentation which, however, is based on the same principles of the bubbler cap.