THE CHARMAT METHOD
Today semi-sparkling and sparkling wines are almost always produced using the Charmat method which differs from the classic method as the fermentation takes place in an autoclave, a large pressurised container, instead of in the bottle.
The result of using this method, both for semi-sparkling and sparkling wines, is a product where the effervescence (the carbon anhydride contained in the liquid) comes from endogenous fermentation.
In the Charmat method carbonation occurs biologically due to the decomposition of sugar by saccharomycete yeasts and, as a result, the natural fragrances of the grapes are better preserved.
Maumèné was one of the first to have the idea of fermenting sparkling wines in large containers rather than in bottles, thereby speeding up the process
|In 1852 he built a machine called an Afroforo which consisted of a tank in which the fermentation took place. Then, once it had cleared on its own, the wine was siphoned off and bottled. However this method was difficult to reproduce on an industrial scale. The Italian Martinotti took Maumèné’s idea and, with some modifications, was finally able to industrialise the process, but still without gaining much approval.
In the end it was a Frenchman by the name of Eugène Charmat who was able to turn Martinotti’s idea into a successful industrial project. His main change was to move away from wooden autoclaves and use steel, coated on the inside with a vitrified glaze which was resistant to attack by wine and sulphuric acids.
Today this technique is known as the Martinotti-Charmat Method, or sometimes the Italian Method.