After thoroughly washing Champagne glasses, one should always dry them with a lint-free cloth.
As a matter of fact, in order to maximize you Champagne’s effervescence, leaving a tiny bit of lint in your glass is paramount. As we all know, popping a Champagne cork reduces the tremendous pressure maintained in the thick bottle and releases the carbon dioxide dissolved in the wine. The gas molecules come suddenly out of solution and must collect together in order to form a bubble. Gerard Liger-Belair, a physicist (or “fizzisist”?) at the University of Reims and the world’s leading authority on bubbles, filmed Champagne using high-speed video and a microscope, and discovered that bubbles can form at a rate of 400 per second. Most bubbles form on imperfections or microscopic particles inside the glass, such as pieces of lint that floated into the glass or were left behind by a towel. Molecules of CO2 collect on the particle until together they become buoyant enough to detach and float to the surface as a single bubble. Another bubble of collected CO2 molecules then forms in its place, resulting in the telltale fine lines racing up through the wine. So for optimal effervescence, we recommend wiping Champagne and sparkling wine glasses with a clean, dry (but not lint-free) cloth before using them.