Czech wine of these festivals in Znojmo, Mikulov, Brno and Mělník will feature samples of hundreds of local wines as well as local music, dancing and cuisine. These wine-festivals take place in big towns apart from the wine-producing areas as well (such as Prague). Czech wine law classifies wine according to the origin of the grapes and the ripeness of the grapes determined by measuring the must weight in the grape juice at the time of harvest. Sugar content is expressed in units of °NM on the Czecho-Slovak Normalised Must-Weight Scale (Czech: "Normalizovaný moštoměr"), which indicates how many kilograms of sugar are
Phenolic content in wine but "resolve" (through a chemical process called polymerization) into delicious and complex elements of "bottle bouquet" when the wine is cellared under appropriate temperature conditions, preferably in the range of a constant . Such wines mellow and improve with age with the tannic "backbone" helping the wine survive for as long as 40 years or more. In many regions (such as in Bordeaux), tannic grapes such as Cabernet Sauvignon are blended with lower-tannin grapes such as Merlot or Cabernet Franc, diluting the tannic characteristics. White wines and wines that are vinified to be drunk young (for examples, see nouveau wines)