What does a pneumatic press use to apply pressure in winemaking?

A pneumatic press utilizes an inflatable rubber tube situated within a perforated stainless steel cylinder to apply pressure during the winemaking process. This design allows the rubber tube to expand when air is pumped into it, creating gentle, even pressure against the grape must contained within the perforated cylinder. The perforations are crucial as they enable the juice to flow out while retaining the solid grape materials.

This method is especially effective for extracting juice without crushing the grape seeds or skins too much, which can lead to undesirable tannins and bitterness in the wine. By applying controlled pressure, the pneumatic press efficiently maximizes juice extraction while maintaining the quality of the final product, making it a popular choice among winemakers.