h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Champagne is not just 'the generic name for any sparkling wine produced in the Champagne region of France'. There are in fact extremely strict rules about how the wine must be made before it is allowed to be called Champagne.

The most significant requirement is that it must be made by the 'Traditional method', often called the 'Champagne Method' for obvious reasons. This is spectacularly complicated & time-consuming because the wine is bottled before refermentation (that's what makes the bubbles). Some poor chap then has to spend months and months carefully turning every single bottle a quarter inch every day - and that's just a part of a process to get the sediment out. However, it does make the highest quality sparkle!

You can also add bubbles by refermenting the wine in a big compressed vat before bottling. Or, if you're a real cheapskate and don't care if the bubbles last more than 30 seconds, you can inject carbon dioxide direct into the bottle of wine.

Sorry - got a bit carried away there. I've just done a wine tasting course so am rather enthusiastic on the subject at the mo!