(Above photo courtesy of Dobbes Family Estate Winery and yep - that's me)
In this part of the wine making process, the grape juice has turned to wine, i.e. the sugar has been turned to alcohol, and we need to separate the grape skins and seeds from the juice. To do so, you have to put on a CO2 meter, a harness, and all-weather gear and climb inside the giant steel tanks. This is a pretty dangerous activity, since loads of carbon dioxide are present, so you get a fan and a spotter to help keep you safe. No one was knocked out by CO2 this year as far as I know.
At this point, the skins have been mixing with the juice in order to create aromas and flavors. This process usually takes ten to 30 days. You can add additives, such as FermAid, to make fermentation go more quickly.
Below is a tank digging photo-story. Click on the title "Digging Out Tanks" in the lower left-hand corner to check it out. Click anywhere on the image for full screen.