Madeira always show a typical malty-caramel taste. This is caused by the heat treatment of the wine, which causes the sugar in the wine to caramelize. The simplest and cheapest type of heat treatment is the method called Cuba de Calor, in which the wine is heated to 40 – 50 ° C using simple heating coils. The most expensive type of warming, called Canteiro, which lasts up to 20 years, is reserved for better qualities. It takes place in the attics of warehouses in barrels of various sizes.
Different grape varieties are used for the production of a Madeira, whereby a basic distinction is made between the noble grape varieties such as Sercial, Verdelho, Bual, Malmsey and Terrantez and the less noble varieties such as Complexa or Tinta Negra Mole.