Racking

To Rack (verb)

Racking is the action of moving wine, beer, or any fermented liquid off the sediment that settles during fermentation. This sediment — sometimes called "lees" in winemaking or "trub" in brewing — can impart off-flavours if the liquid is left sitting on it for too long, so racking is an important step in producing a clean, well-finished drink.

Syphoning Method

In small-scale production, racking is usually achieved by syphoning. A tube is placed into the fermenter with its lower end positioned just above the sediment. As liquid flows through the tube into a clean vessel below, the syphon stops automatically before the sediment gets sucked up — provided you have positioned the tube carefully.

Tips for Syphoning

• Move the fermenter to a higher surface an hour or so before racking, so any disturbed sediment has time to resettle.
• Keep the end of the tube just above the sediment layer — do not push it to the very bottom.
• Tilt the fermenter gently towards the end to collect as much clear liquid as possible.
• Avoid splashing the liquid into the receiving vessel, as this introduces oxygen which can cause oxidation.

Conical Fermenters

Larger-scale and professional producers often use conical fermenters. These have steeply sloped bottoms that collect the sediment in a cone at the base. The very bottom of the cone is fitted with a tap, which allows the sediment to be drained away while leaving the clean liquid in place above it.

When and How Often to Rack

Most home winemakers rack at least once after the initial vigorous fermentation has finished — typically after one to two weeks. A second racking a few weeks later helps ensure clarity and removes any further sediment that has settled. Some wines benefit from a third racking before bottling, especially if they are being aged for several months.

Beer is usually racked into a secondary fermenter or directly into a bottling bucket. Because beer fermentation tends to be shorter, one or two rackings are generally sufficient.