Grape Cap Winery Punch
notes: label: Description
content: When Joel Peterson of Ravenswood Winery, in Sonoma, California, made his first Zinfandel wine in 1976, he used dry-farmed (non-irrigated) grapes from old vines and fermented them in open-top casks. He also used this 5-foot-long aluminum tool made by a local metalworker to “punch down the cap.”
label: Description
content: During fermentation, a solid mass of grape skins, stems, and seeds (the “must”) rises to the top of the fermentation vessel, typically a wooden cask or metal tank. The cap must be broken up and stay moist to benefit the wine’s color and flavor, which results from the mixing of yeasts into the must and the dissipation of bacteria-friendly heat that occurs during the course of normal fermentations. The winemaker has to punch down the cap several times a day while fermentation is underway.
label: Description
content: To carry out a punch-down, the winemaker stands above the tank and, with a great deal of strength, shoves the punch into the cap, breaking it apart and keeping the must moving. Many modern winemakers prefer using electric pumps to do “pump-overs” in closed tanks or rotary tanks to swirl the wine, both the mechanical equivalent of the old-style punch-down by hand. The open tank punch-down remains the artisanal practice to date, and it is still used by winemakers from Oregon to France.
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content: Work and Industry: Food Technology
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content: Food
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content: FOOD: Transforming the American Table 1950-2000
label: Exhibition
content: Food: Transforming the American Table
label: Exhibition Location
content: National Museum of American History
creditLine: label: Credit Line
content: Gift of Joel Peterson
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2011.0150.01
label: accession number
content: 2011.0150
label: catalog number
content: 2011.0150.01
objectType: label: Object Name
content: punch
physicalDescription: label: Physical Description
content: metal (overall material)
label: Measurements
content: overall: 58 in x 9 1/2 in x 12 1/2 in; 147.32 cm x 24.13 cm x 31.75 cm