On display at Sebastiani Vineyards & Winery are twelve wood carvings – one for each month of the year – each depicting an important part of the winemaking lifecycle. We’re diving into each month and where winemakers have traditionally kept their focus during that time in our editorial series, The Vintner’s Calendar.
Sebastiani’s Vintner’s Calendar wood carving for October illustrates the process of fermentation.
The process of fermentation in winemaking is turning grape juice into an alcoholic beverage—wine. More specifically, the yeast converts the sugar from the grapes into alcohol and carbon dioxide along with other by-products. More sugar in the grapes means that the wine will potentially have a higher alcohol level.
Red wines are typically fermented in contact with skin, seeds, and stems which is what makes them tannic. The skin, seeds, and stems also what give red wine its color. White wines on the other hand, are not usually fermented in contact with the skin of the grapes. Rose wine is commonly made with red grapes, but the skins and other components of the grapes are removed early in the maceration process.
Malolactic fermentation is a secondary fermentation where malic acid is converted into lactic acid. For this process, bacteria instead of yeast aid the fermentation. This reduces some of the acidity which makes the wine taste creamy and buttery. Most red wines and some white wines such as Chardonnay and Viogner will go through the process of maloactic fermentation.