Must: the first stage in the transformation of grape bunches
How do you get the must?
Once the grape harvest is over, the time comes to squeeze the grapes. This process takes place after the wine maker controls and separates the grapes harvested according to their place of growth and quality. Afterwards grapes will be pressed (white wines are used to extract the must), a procedure that has different times for white, red and rosé wines. In fact, in the case of white or rosé wine, after slicing, the pomace and the grape must are immediately separated from the must. Red wine, on the other hand, has a slightly different procedure.
The must, addressed to become red wine, must ferment together with the pomace for a period that goes from 8 to 14 days to acquire the characteristic dark red color. As for rosé wines, there are two different ways to get them. In the first case, the red grapes are mixed with the white ones. In the second case, however, a white vinification of unpigmented red grapes (Pinot Grigio) is done.
Must is therefore what is obtained after the grape baking, when the skins and pulp have not been squeezed yet. Generally, almost 70% of the grape will become grape must, while flower must account for about 60-65% of the weight of the whole bunch. However, the yield of grapes depends heavily on so many factors. The seasonality, variety and degree of ripening of grape berries may increase or decrease the amount of must obtained after pressing or bottling. In the case of white wines, the fast separation of the must from the pomace is necessary also to avoid the extraction of tannins.
Extra virgin must
Making wine is an art that requires attention to small details and a good knowledge of production processes. Every step is important, and any mistake, even of small one, can compromise the quality of wine in the end. But, going back to the production of wine, it must be said that the must also is affected by other changes. In fact, after the must is separated from the solid parts (the operation that brings the blotchy name), it has to be subjected to the blur (also called defecation), which is nothing more than a clenched process. The final result of this operation is the elimination of the majority of the lees.
Often, to help the must to become clearer, the enzyme is used to clarify white musts. Few people know that white wine can also be produced with red grapes. In fact, the one that gives color to wine is just the peels and, when it is eliminated during the bleeding phase, the must remains clear. This first quality must is often called “the good part” (or “extravergine” must) in the jargon of wine producers. The steps that follow are the decanting, filtration and centrifugation in order of processing.
The separation of the must from the pomace. How, when and why it is necessary
Destemming and pouring are operations that have a great importance in the production of quality wines. An excellent white wine has a pleasant freshness, a good acidity and a fruity, fine and distinct scent. To achieve this, the pressed grape must be immediately separated from the grape juice, and by doing so, the process is easier, as well as avoiding any onset of oxidation.
The pomace is porous and airy and this could contribute to the oxidation of wine. Once separated, the must rests in large, temperature-controlled, stainless steel at very low temperatures (between 5 and 10 ° C). After about 12 hours the impurities will go down and the purified part can be aspirated by mouthpieces. Lately, many producers have begun to add bentonite to the must at fermentation to allow the protein to be eliminated and, once fermented, the separation of the wine from the remaining lees.