with the skins, and winemakers seek to correct this by pushing down the cap (either with equipment or the traditional method of treading with their feet) or by pumping wine out from under and over onto the cap. This process of "pumping over" or "punching down" the cap is done often throughout the fermentation process, depending on the extent of maceration the winemaker desires. An efficient and modern method of maceration is the "pneumatage process" in which compressed air or gas is sequentially injected into the juice. The bubbles created during the pneumatage process uses gravity and the weight of the juice to circulate the wine juice with the cap of skins and grape solids allowing for greater extraction of aroma, coloring agents and tannins to diffuse into the wine juice ("must"). Benefits Depending on the varietal, the process of maceration can help bring out many flavors in the wine that would otherwise be lacking. It can enhance the body and mouthfeel for many wines, as well as strengthen the color. Greater extraction can add to the complexity and life expectancy of the wine by developing more complex tannins that will soften over a longer period of time. With these benefits does come the risk of developing various wine faults, such as the development of acetic (or "volatile") acidity. Too much extraction can also increase the harshness of some tannins to where the wine is not very approachable to most wine drinkers. Other processes One classical method of maceration is grape treading or pigeage, where grapes are crushed in vats by barefoot workers. The process of cold maceration or cold soak is where temperatures of the fermenting must are kept low to encourage extraction by water and added sulfur dioxide rather than relying principally on heat and alcohol to act as a solvent. This technique was popular in the production of Burgundy wines in the 1970s and 1980s but there is still some debate among oenologists about the overall benefits to and resulting quality of the wine. Carbonic maceration is the fermentation of whole clusters of unbroken grapes in an atmosphere saturated with carbon dioxide, which prevents traditional yeast fermentation. It is a process different from what is commonly referred to in winemaking as "maceration". References Winemaking Wine terminology de:Mazeration fr:Macération