When fermenting wine on the skins as you would with fresh red grapes or as you would with one of our Cellar Craft or WinExpert wine kits which include the two liter packet of crushed grape skins a cap of grape skins, stems and seeds will float to the top of your primary during fermentation. To obtain the flavors and colors present in this mass of pulp floating on the top of your fermenter you need to break up this mass and push it under the surface so that it stays moist. This breaking up of the cap and the process of pushing it under the surface is called punching down.
As mentioned previously, your wine will benefit from this process with more flavor, astringency and a richer color.
Other benefits derived from the punching down process include helping to keep bacteria from forming on this crusty surface, yeast which is trapped in the crust is mixed back into the must, punching down introduces oxygen into the must which provides a healthy environment for your yeast to thrive, and it helps dissipate heat which can build up during fermentation (warmth provides a healthy environment for bacterial growth).
The use of a stainless steel spoon (slotted preferred) or a masher of some type works well. Break up all the clumps so that the surface of your wine is smooth and all floating matter is thoroughly moist when done. Punch your wine down as soon as you have pitched your yeast and do so every six to eight hours throughout the primary fermentation process.
Maintain a temperature slightly cooler than maybe you normally do during primary fermentation. Keep your ambient temperature around 65 degrees Fahrenheit if possible and try hard to not let your temperature exceed approximatly 70 degrees.
As fermentation slows there will be less carbon dioxide being generated (the carbon dioxide rising to the surfact of the wine must is what causes the pulp to float to the surface). When the mass of pulp disappears (sinks) it is time to press out the pulp and remove it from the fermenter.
BlueStem Winery would like to be your source for all the wine making supplies, home brewing ingredients, WinExpert wine kits and Cellar Craft kits that you need. We stock an extensive array of homebrew equipment and equipment for making wine in addition to a large inventory of WinExpert kits and an even larger supply of Cellar Craft wine kits. So, if you are a veteran home brewer and need to order home brew supplies or whether you are a novice to home winemaking and need some help getting started, we can provide the help you need.