Champagne is made strictly in the Champagne region of France. Only three types of grapes can be used for champagne, Pinot noir, chardonnay and Pinot Meunier. Most champagne is made of Pinot noir and Chardonnay. If champagne is labeled as Blanc de Blanc then it is made completely of Chardonnay grapes. If it is labeled Blanc de noir then it is made of Pinot noir and Pinot meunier grapes. Do not get confused with a label that states methode champenoise. This sparkling wine was not made in champagne but uses the same winemaking method that they use in champagne.
Methode champenoise or methode traditionelle involves two fermentation and all champagne and high quality sparkling wine will be made in this manner. A still wine is first produced like making any normal wine. A sparkling base will be made using a blend of different fermentations until the desired aroma and flavors are met. This base wine is bottles and the liqueur de triage is added, a solution of sweetened juice and yeast. The bottles are corked and a second fermentation takes place in the bottle. In order to get ride of the yeasts the bottles are riddled. The traditional riddling technique takes months where the bottle is gently tilted on racks until all of the yeast has collected at the neck of the bottle. Disgorging then occurs. The neck of the bottle is dipped in liquid nitrogen or another freezing agent and uncorked, the pressure expels the yeast, and the bottle is topped up with some additional wine and quickly corked again. A small amount of CO2 is lost but there still is enough gas in the wine to create lot of lovely bubbles in your champagne.
Yeasty and toasty notes generally characterize champagne flavor and aromas. This is due to that second fermentation where the yeast imparts its flavor to the wine. This is also known as leaving the wine on its lees. Champagne will be aged for a determined amount of time. Most Champagne is non-vintage (NV). SO there will not be a year on the label. Vintage champagnes are produced only on exceptional years and if you are lucky enough to come across one then that should be a fantastic drink. Vintage Champagnes are generally quite a bit more expensive. Though if you buy a recent vintage Champagne and cellar it for some years that would be an excellent investment. Personally my wine never really lasts that long.
Less expensive sparkling wine is made using a tank method, where the second fermentation takes place in a tank; the wine is then filtered and bottled. The least expensive method is when the wine is carbonated. The traditional champagne flavors and complexity of the wine is quite inferior as the important aromas imparted form the yeast during that second fermentation is lost. Each type of champagne has its uses but true Champagne and sparkling wine made in the methode champenoise is exceptional. There is quite a bit of sparkling wine made in the methode champenoise that is excellent and also affordable. So go out there and start drinking some bubbly!