One regular, and critical task in the winery, and one of my favorites, is punch-downs. Punch-downs refer to breaking up and submerging, literally pushing down, the cap of skins and seeds that float, or are pushed to the top of a tank. This is what makes red wine; by mixing up the grapes in their juice, skin phenolics are extracted, color and tannins are imparted and the juice develops character. As the juice ferments, the berries are pushed to the top by carbon-dioxide.
When fermentation is in full swing, we punch-down four times a day. In the morning a cloud of C02 can be seen when you first break the cap, as the warm gass breaks through to the cold air. The cap is three feet thick, and rolls like a wave when you push on one side. Traditionally this is all done by hand, with a metal paddle, but we are afforded pneumatic arms the take much if the work out of the job. Still, we run around, trying to cycle through a dozen tanks.
The point of a punch down is not just to extract color and tannins.
Fermentation, through the mechanism of CO2, stratifies the tank, and the top of the juice can be several degrees warmer than the bottom. Mixing the tank helps keep the temperature even. And it does so gently, which is important to Pinot Noir, as it benefits from careful handling.
What I love about the punch-downs is seeing how each tank is unique, depending on the vineyard or lot or stage of fermentation. Some tanks give off a very fruity aroma, as they go through the cold soak. As the juice turns to wine, fermentation imparts new scents to the wine; some tanks give off a savory, gamey bouquet, others maintain a their primary fruit character. Each tank is different, and a map of aromas and bouquets in the winery has developed in my head.