The harvest consists in harvesting the grapes when it is fully ripe. The period indicatively runs from August to October. In fact, the vines do not all have the same reproductive cycle.
Some of them are precocious and begin to sprout at the end of winter. At the end of June the fruit set is already in place and the ripe berries are ready in August. Others, however, have longer times also depending on the temperatures of the regions in which they are raised. Another substantial difference is between white and red.
The whites must be accompanied by good acidity. The collection of white grapes is aimed at obtaining wines with these characteristics. The white grape must requires controlled temperatures so that it does not undergo oxidative processes. The color in this case would be compromised.
Crushing crushers to get the must
The pulping machines are machines that allow the crushing of the grapes. The destemming function allows to separate the berries from the stalk. The quality of the wine depends on this step.
In vinification in white the grapes are softly pressed separating the solid part from the juice. In red and rosé vinification, the juice and the solid parts are left to ferment together to allow the extraction of color, anthocyanins and polyphenols.
In the fermentation autoclave the skins will tend to form the hat. A re-assembly system keeps the solid mass immersed. At this point after 10-15 days the grape must is filtered to remove the pomace. They will be used as fertilizer or sent to the distillery. The distilled marcs will give the grappa.
Classification of grape must
With the abbreviation T.A.V. means the alcohol gradation actually carried out of the grape must. In this case the rate must be equal to or less than 1%. Depending on this value, the types of must have their own classification.
Partially fermented grape must is the one whose T.A.V. it has a value greater than 1% but less than 3/5 of the alcoholic strength potentially reachable by complete fermentation.
The mute grape must is obtained by adding sulfur dioxide. Practically, the alcoholic fermentation stops.
The mistella is obtained by adding alcohol or wine spirits to the must whose alcohol content is at least 12 degrees. Fermentation is stopped, obtaining a minimum alcohol content of 16% and a maximum of 22%.
The cooked must, on the other hand, is obtained by removing the water from the grape must and heating it. In this way, the sugar concentrate measured with the densimeter increases.
Grape must: The importance of sulfur dioxide
Sulfur dioxide provides a valuable contribution during the wine production process. Unlike what is commonly thought, it is used to an adequate extent and is not harmful to health. The limits of use are laid down by applicable laws in force.
The amount used varies according to the health of the grapes. Well harvested grapes that have not been excessively abused will allow the use of a minimum quantity of sulfur dioxide. On the contrary, grapes at risk of early fermentation due to the breaking of the grapes must be preserved.
The white grape must is particularly delicate. It could undergo oxidative processes with browning of color. The function of sulfur dioxide is useful for blocking the action of yeasts and bacteria responsible for this phenomenon.