To explain how wine is made would take an exhaustive length of time and study volumes of reference books. However, we will describe basically the main differences in techniques and practice in order to give you a general idea on the subject. Vinification occurs thanks to the complex action of certain yeasts (usually inside the grape) transforming the sugar into alcohol and causing the so-called alcoholic fermentation. During this phase a lot of chemical processes happen giving the wine its basic structure. In spite of the fact that the alcoholic fermentation is a natural process, some particular and specific yeasts are added to the must in order to obtain an optimal product. Now will be taken into consideration red, white and rosé vinifications, mention will also be made regarding the techniques used in making spumante: Metodo Classico and Charmat as well as some hints about malolattica's fermentation and its importance.
Vinification in red
With the vinification in red, the solid parts of the grapes are kept together (skin and seeds and so called grape seed) in macerating with the must. Before pressing the grapes, the stalks are removed so as to avoid giving an astringent taste and lowering the concentration of the colour. The longer the skin is left to macerate the more intense the colour of the wine will be. Generally the time in macerating for light red wines is 4/5 days to a maximum of 4/5 weeks for more tannic and concentrated red wines. At the end of this period, the solid parts are taken away from the must and pressed. The pressing will produce a very tannic and coloured must which is vinified separately and added to the flower wine in a specific quantity in order to give it a thickness. The vinification is carried out under very meticulous controls, to decant and to fill up so that at the end of all these processes the wine is ready to be bottled.
Vinification in white
In comparison with the red, the white vinification differs basically because the solid parts are taken away and not left to macerate with the must. As a result the wine is not charged with tannin and coloured substances. For this purpose, sophisticated wine-presses equipped with inner tube chambers so as to avoid the solid parts falling into the must. The marcs are pressed immediately with a particular calibrated pressing machine and the result of it is added, all or in part, to the must. Because of very little presence of tannin the white must is very delicate and needs a lot of attention. For the vinification in white even red grapes can be used: an example the Pinot Nero is often used in producing white wines. Sometimes, in order to obtain a better structure to the wine a short maceration of the stalks is practised.
Vinification in rosè
Basically this is a vinification which stands in between the other two methods used. Red grapes are used for the vinification taking care in leaving, for a short period, the stalks macerating with the must so as to give a very delicate colour to the wine.
Metodo Classico
The Metodo Classico or Champenois, is the vinification method practised in producing the best Spumanti. The starting point is the choice of an already mature wine, often a cuvèe (or mixture) of very selected wines. Borgognone's bottles are used to fill them up with the addition of selected yeasts. To seal the bottle a particular crown cap with a roomy space inside able to hold all impurities, is used. The wine starts rifermenting in the bottle and, this process called “on the yeast” can even last for years. The next step will be to store all bottles in the racks so called “pupitres” which allow, due to their ogival holes, to vary the inclination of the bottles. At the beginning the bottles lie in a horizontal position and, day by day, gradually they will be tilted, head down, to reach, at the end, a vertical position in order to allow all impurities todeposit into the room in the crown cap. A the end of this procedure, the impurities, together with caps are taken away and after having replaced the liquid, they are sealed with the classical spumante cork.
Metodo Charmat
The difference between Metodo Classico and Metodo Charmat is that the last method does not imply for the spumante to refermented in the bottle. The wine is kept in a huge hermetic sealed container so-called autoclave. This technique can reduce sensibly the cost of the operation especially when big quantities are involved. The metodo Charmat, when used in a skilful way, can produce a very good spumanti.
Fermentazione malolattica
The fermentazione malolattica is not a technique in vinification but it is a natural phenomenon which happens generally at the beginning of spring. The increase in temperature favours this very slow fermentation in transforming the malico's acid into lactic acid. The result will allow the wine to soften due to the fact that the lactic acid is not as astringent as the malico acid. This fermentation plays an important role in defining the character of the wine. All white and mainly full bodied red wines must do the malottica fermentation: on the other hand this type of fermentation is not desirable when the aim is to obtain fresh and acid wines, especially with whites ready to drink. In the right conditions and with a not excessive concentration of sulphur dioxide ( used as disinfectant during the vinification process) the malottica fermentation can happen spontaneously. Otherwise it can be induced by adding selected yeasts.
