The method used to produce Lambrusco is known as the Charmat method or the tank method. This particular carbonation method is also commonly used in the production of prosecco. As an expert sommelier and brewer, I can provide you with a detailed explanation of how this method is employed to create this popular sparkling wine.
In the Charmat method, the winemaker starts with a base wine that is not yet sparkling. This base wine is typically made from the Lambrusco grape variety, which is known for its vibrant acidity and fruity flavors. The winemaker then adds a mixture of sugar and yeast to the base wine in a large pressurized tank.
The addition of sugar serves two purposes in this process. Firstly, it provides food for the yeast to consume during fermentation. As the yeast consumes the sugar, it produces alcohol and carbon dioxide as byproducts. Secondly, the sugar also contributes to the sweetness of the final wine, as some of it remains unfermented.
The tank used in this method allows for the carbon dioxide produced during fermentation to be captured and dissolved into the wine, creating the desired sparkling effect. The pressure inside the tank ensures that the carbon dioxide remains in solution, resulting in a wine with effervescence.
The Charmat method is often preferred for the production of inexpensive examples of Lambrusco and prosecco due to its efficiency and cost-effectiveness. The large pressurized tanks used in this method allow for larger quantities of wine to be produced at a time, making it well-suited for mass production.
One of the advantages of the Charmat method is that it allows for the preservation of the wine's fruity and floral aromas. Since the secondary fermentation takes place in a closed tank, there is minimal contact with oxygen, which helps to retain the wine's aromatic qualities.
However, it is important to note that the Charmat method does not typically result in wines with as fine and persistent bubbles as those produced using the traditional method, such as the méthode champenoise. The bubbles in Charmat method wines tend to be larger and less refined.
To summarize the Charmat method, it involves the addition of sugar and yeast to a base wine in a large pressurized tank. The fermentation that occurs in this tank creates carbon dioxide, which dissolves into the wine, giving it its sparkling character. This method is commonly used in the production of Lambrusco and prosecco, and while it may not produce the most refined bubbles, it allows for the preservation of the wine's fruity and floral aromas.