Bubbles: it’s a magic word, almost synonymous of celebration and conviviality, under whose hat very different wines are included – from the majestic Champagne to the graceful Pét Nat – the result of equally different production methods that have one thing in common, refermentation, to which we owe that perlage that we like so much.
The mother of all sparkling winemaking systems – ça va sans dire – is the Champenoise or Classic Method, developed over several centuries in the Champagne region of France. Leaving aside the historical role attributed to the abbot and cellarman Dom Pérignon in the seventeenth century, the champenoise as we know it today was “certified” in 1936, at the end of long legal battles, when the denomination of controlled origin (AOC ) was established thus protecting the production method. Since 1995, all sparkling wines produced in France out of Champagne region are called Crémant, while for all the others outside the French borders we generally refer to the classic method.
The classic method involves the assembly of different grapes (cuvée) and often also of different vintages, to create an organoleptic balance that, on the one hand, softens any imperfections of the individual crus and, on the other, represents the stylistic code of each cellar.
In specific years, producers can choose to make wine with grapes coming for min 85% from the same harvest or, in very rare and therefore extremely valuable cases, with grapes from a single vineyard. When this happens, we refer to Millesimée and the bottles indicate the year of the harvest.
If the grapes of the cuvée are all white berried we will have a Blanc de blancs, if it is black berries vinified in white we will have a Blanc de noirs.
Moving on to the stages of vinification, the champenoise method involves a first complete fermentation of the base wines of the cuvée which are then bottled during the following spring.
Before bottling, the liqueur de tirage is added to the wine, a mixture of wine, cane sugar, selected yeasts and mineral salts, necessary to activate the refermentation process in the bottle which is what gives start to the bubbles. The bottles are then closed with a crown cap and put in horizontal position (second fermentation).
The bottle refermentation generally lasts a few weeks while the subsequent residence time of the wine on the exhausted yeasts depends in part on the reference disciplinary, in part on the stylistic choices of the cellar master. Simplifying a little, we can say that the longer the stay is extended, the more the wine acquires depth and complexity, with a more elegant and persistent perlage.
Once the ageing is complete, it is time for the separation of the wine from the lees of the yeasts, which takes place through remuage, that is the progressive rotation of the bottles up to the vertical position to clarify the liquid and make the lees flow into the neck.
At this point, the neck of the bottles is made to freeze in a refrigerating bath and subsequently the latter are straightened and uncorked, allowing the gas pressure to release the frozen residue. This is the moment of disgorgement or dégorgement.
Last step before closing the bottles with the caged cork (necessary to resist the pressure of carbon dioxide): adding the liquer d’expedition, a mixture of wine and sugar and other secret elements, the recipe of which varies from cellar cellar given the final result to obtain.
The proportions of the liquer d’expedition change according to the degree of sweetness to be achieved, ranging from Doux (50 grams of sugar per liter) to Extra Brut (maximum 6 grams of sugar per liter), passing through a series of intermediate steps.
We then refer to Pas Dosé or Zero Dosage, if the grams of sugar per liter are less than three.
– The Editorial Board, August 4th 2020