On our previous post we started our journey into the world of Italian spumante by covering the basics, very briefly touching upon Champagne, introducing the two main processes to make a natural sparkling wine, the Champenoise or Classic Method and the Charmat-Martinotti or Italian Method, and finally going through the main steps of the Classic Method production process. So, if you missed that post, you may want to go through it first and then dive into this second chapter of the “spumante saga” 😉
On today’s post we will briefly discuss how and when the Charmat-Martinotti Method came to be, we will then point out the main differences between the production processes for the Italian Method and the Classic Method and finally we will go through the main steps of the Charmat-Martinotti Method, including its variant used in the production of Asti Spumante.
Let’s therefore start with some history. The development of the most commonly utilized alternative process to make a sparkling wine, the so-called Martinotti Method or Charmat Method or even Italian Method, took place at the end of the XIX century, precisely in 1895 when Federico Martinotti, who was in charge of the Royal Enological Station in Asti, invented a steel pressurized and refrigerated vessel known as “autoclave” that is used to make Italian Method spumante wines. This alternative process is also known as “Charmat Method” because a French engineer by the name of Eugéne Charmat adapted the design of Martinotti’s autoclave to suit industrial production of sparkling wine and rolled out the product in 1907. Considering the contributions made by both such gentlemen to devising such alternative production process, I think the proper way to identify it would be “Charmat-Martinotti Method.”
Now, let’s get a little more into the specifics of how the Italian Method differs from the Classic Method and what this means to you if you want to buy a bottle of wine made according to one versus the other of such production processes.
First of all, let’s start by saying that two of the most renown Italian Method spumante wines are:
- Prosecco (although there are a few producers who also make very good Classic Method Prosecco’s, such as Valdo‘s Prosecco Brut Metodo Classico Numero 10 DOCG). Prosecco is made prevalently or exclusively from partly-aromatic Glera (also known as Prosecco) grapes in either one of the following two DOCG appellations of the Veneto region: Prosecco di Conegliano Valdobbiadene DOCG or Prosecco dei Colli Asolani DOCG as well as in the more loosely regulated DOC appellation Prosecco Spumante DOC, which stretches between Veneto and Friuli; and
- Asti Spumante, which is made exclusively from aromatic Moscato Bianco grapes in Piemonte’s DOCG appellation Asti Spumante.
Generally speaking, Prosecco is made as a dry wine: according to applicable regulations, it may be produced in all variants between Brut (less than 15 gr/lt of residual sugar) and Demi-Sec (33 to 50 gr/lt of residual sugar, which would make it fairly sweet tasting), but your best bets are in the Brut, Extra Dry (12 to 20 gr/lt of residual sugar) or Dry (17 to 35 gr/lt of residual sugar) versions.
Asti Spumante, instead, is typically a sweet dessert sparkling wine, with over 50 gr/lt of residual sugar. So, do not serve Asti Spumante with appetizers – just keep it chilled until the end of your meal and pair it with a dessert.
On our previous post, we saw how two key features of the Classic Method are its in-bottle refermentation process of the base wines and then the generally long period of time spent by Classic Method wines aging on their lees before their being shipped off to wholesalers and retailers worldwide.
What makes Italian Method sparkling wines generally less expensive than Classic Method wines and different in terms of aromas and taste is mainly their different production process. For Italian Method wines, this is much shorter because refermentation of the base wine(s) takes place in a pressurized autoclave instead of in-bottle and so does their much shorter aging time on their lees. Essentially, after the production of the base wine(s), the entire refermentation, aging and bottling phases of an Italian Method spumante all take place in an isobaric, refrigerated environment inside an autoclave, which dramatically shortens production time.
In real life, what does this mean to you? Well, for starters it means that if you buy an Italian Method spumante (like Prosecco, for instance) it will feel different both in the nose and in the mouth compared to a Classic Method sparkling wine (such as a Franciacorta or a Trento). This is because, by aging often for years on their lees, Classic Method wines develop a number of intriguing secondary and tertiary aromas, such as the quite notorious bread crust or “just baked bread” aroma.
Because of the different production process and the much shorter aging time, most Italian Method wines have fewer (or less distinct) secondary and tertiary aromas, but make up for it by being generally made from aromatic grapes (as is the case for Asti Spumante, which is made from aromatic Moscato Bianco grapes) or partly-aromatic grapes (such as Glera, also known as Prosecco) and therefore emphasizing the primary or varietal aromas of the grape(s) their base wine(s) are made out of.
In other words, chances are that if you pop a bottle of Classic Method sparkling wine you will get a broader, more complex aromatic palette and mouth feels while if you pour a few glasses of a quality Italian Method spumante you will likely get a fresher, simpler wine with quite distinct flowery and fruity aromas.
Other differences between a Classic Method wine and an Italian Method one are that the former generally has a color that is warmer in hue, a finer perlage and more structure than the latter. Regarding structure, this is a bit of a generalization as it is essentially dependent on the grape varieties that are used for making the base wines, so the point holds true especially for Classic Method wines that have Pinot Noir in their cuvée (a grape variety that is known to confer structure to the wine) and, even more so, for Blanc de Noirs.
Let’s take a little detour here: on our previous post we said that the base wines of a Classic Method sparkling wine are made from all or some of the following grape varieties: Chardonnay, Pinot Noir and Pinot Meunier (as far as Champagne is concerned), which last grape variety in Italy is generally replaced by different grapes, such as Pinot Blanc (as far as Italian Classic Method spumante is concerned). So, what we could call the “kosher” version of Champagne or Classic Method wines is made out of a cuvée produced from all three of such base grapes. However, there are two main variants from the “kosher” version, that are known as Blanc de Blancs and Blanc de Noirs.
The former is a wine made exclusively out of permitted white-berried grapes (in the case of Champagne, this means a Chardonnay-only wine), which is generally fresher, gentler and of lighter body, very suitable for instance as an appetizer or paired with delicate flavored seafood.
The latter is just the opposite, that is a wine made exclusively or prevalently out of permitted black-berried grapes (again, in the case of Champagne, this means Pinot Noir and/or Pinot Meunier), which is generally a more structured, more complex wine that is more suitable to be served with an appropriate pasta dish or even main course.
Although we will provide a more in depth overview of what a proper wine tasting should entail in a future post, I think it is important to point out certain distinctive features that everyone with an interest in wine can have fun identifying and assessing in a sparkling wine:
- Color: this varies depending on the grapes used in the base wines, but it is one of the characteristics that should always be appreciated, be it a warmer straw or even golden yellow color of a well-aged Classic Method wine or a paler straw yellow, sometimes with greenish hints, of an Italian Method wine;
- Perlage: this is the key feature to be assessed in a sparkling wine, which oftentimes either makes or breaks the wine – what you are looking for here is the three distinct characteristics of a quality perlage: (i) fine-grained bubbles; (ii) abundant bubbles forming uninterrupted chains from the bottom of the glass to the surface; and (iii) long-lasting formation of new chains of bubbles;
- Bouquet: although fine-nosed wine tasters can go wild identifying the slightest hints of this or that, anyone can take pleasure in picking up the scents of a good sparkling wine and trying to identify some of the more distinct aromas, such as bread crust or yeast, apple, almond or wild berries that may be present in a Classic Method wine or the flowery, fruity notes of a Prosecco, often reminiscent of white flowers and pear or again the sweet aromas of sage and peach of an Asti Spumante.
Before we get to the description of the main steps of the Charmat-Martinotti Method, a few practical pieces of advice to maximize your sparkling wine tasting experience (by the way, these apply to any sparkling wine, regardless of its being a Classic Method or an Italian Method wine):
- The proper glass to serve a sparkling wine (except only the sweet ones, on which see below) is a flute, not a cup: this is because the elongated and narrow shape of the flute both emphasizes perlage and concentrates the fine aromas in the nose;
- While we are at it, much to Francesca’s dismay (she just loooves her tinted glasses), all glasses you serve wine in, regardless of it being sparkling or still, red, white or rosé, must be made of clear glass or crystal: no matter how “cute” the tint of those pretty glasses you have sitting in that special cupboard, tinted glass is a no no because it kills right away one of the most important features of a wine: its own color!
- Ideally, your flutes should not be washed with soap, you should just use hot water instead and they should be dried using a natural fiber cloth (such as cotton or linen): this is because, in order for perlage to be at its best, those chains of bubbles need to hang on to something inside the glass, so minuscule lints of cotton or linen are just perfect to maximize your favorite spumante’s perlage, while an ultra-clean, super shiny inside of the flute is going to penalize it.
- Finally, the proper glass to enjoy an Asti Spumante or any other sweet sparkling wine is instead a cup with a wide, shallow bowl, because its larger opening tames a little bit the generally exuberant varietal aromas, while its shallower depth is not so detrimental to the often coarser, less refined perlage of that kind of sparkling wines.
Main Steps in the Charmat-Martinotti Method Production Process:
- Soft pressing of the base wine grape(s)
- Treatments of the must (e.g., clarification and application of sulfur dioxide)
- Fermentation of the base wine(s) by the addition of selected yeast
- Where necessary, blending of the base wines
- Transfer of the base wine(s) into a pressurized, refrigerated autoclave with the addition of sugar and selected yeast
- Refermentation in autoclave, which makes the wine bubbly because the carbon dioxide created by the yeast as a byproduct of alcoholic fermentation remains trapped inside the pressurized autoclave and dissolves into the wine
- Brief period of aging on the lees in autoclave (generally, just a few months)
- Isobaric stabilization and filtration, to remove the lees
- Isobaric bottling and closure
The production process of a sweet Asti Spumante is basically the same as that described above, except that Asti Spumante undergoes one single fermentation phase, directly in autoclave, where yeast activity is inhibited by dropping the autoclave temperature when the wine has reached the desired low alcohol by volume and high residual sugar levels.
That’s all for now. On the next post, we will chat about some of what we believe to be among the best Classic Method spumante wines made in Italy that are available on the market, especially for their price/quality ratios.