The video attached shows how we rack juice (fermentation has not begun yet) off solid material just after the initial press. To rack is to decant or draw the juice (or wine, at later stages of the process) off of solid material to clarify the wine and to maintain balance. Racking occurs just after pressing - for whites, pressing happens before fermentation, and with reds, after the juice has fermented and become wine - after the secondary or malolactic fermentation is complete, and at any time during the process of elevage (the aging of the wine) when the winemaker believes the wine will benefit (the introduction of air when the wine is moved from one vessel to another to help round out tannins or help with reductive characteristics in the wine, and to remove any remaining schmutz left behind.
In the last few weeks - in addition to pressing and racking the first whites of the ‘22 season - we have racked 2021 vintage wine off the primary lees (the red light is red wine illuminated by a flashlight held underneath it running through a site glass). The watch glass is attached to a valve and a bulldog pup so that we can see when we have hit solid material that we want to leave behind.
After this initial racking is completed, we inoculate (in 2022 we are adding yeast to a large tank of Albariño, but letting the dominant strain of yeast in the winery environment ferment a 25-gallon drum of the same juice, in a process called native fermentation), the juice with a yeast strain that adds specific flavor, aroma, and textural components to the wine. Adding yeast to tanks gives us a little more surety that the wine will actually ferment all the way to dryness (inadvertently sweet red wine really sucks!) in addition to the specific organoleptic qualities that we want the yeast to impart.
Wine Glossary: Racking