Cold-pressed juice
Making cold-pressed juice is a two-step process. The first stage is to shred the fruits and vegetables into a pulp. Typically the shredding process uses a steel rotating disc. Produce is loaded into a large hopper feeding tube and typically falls into a filter bag. The second process is the hydraulic press; this exposes the shredded produce to extreme pressures between two plates. The pressure causes the juice and water content from the produce to drip into a collection tray below, leaving behind the fibre content in the filter bag. The fibre left behind is generally composted, recycled in food products or discarded.
Winemaking
Pressing is the act of applying pressure to grapes or pomace in order to separate juice or wine from grapes and grape skins. Pressing is not always a necessary act in winemaking; if grapes are crushed there is a considerable amount of juice immediately liberated (called free-run juice) that can be used for vinification. Typically this free-run juice is of a higher quality than the press juice. Pressed juice is typically lesser in quality due to the release and increase of total phenolic compounds, as well as browning index and the C6-alcohol levels. These compounds are responsible for the herb-like taste perceived in wine with pressed grapes. However, most wineries do use presses in order to increase their production (gallons) per ton, as pressed juice can represent between 15%-30% of the total juice volume from the grape.