Estufas

Estufas (heated stores for ageing Madeira wine) first appeared on this island in 1794. They were banned by edicts of the governor and captain-general of 13 August 1802 and 6 November 1803, but resumed operation under a royal order dated 7 May 1804.

Estufas are intended to give wines an appearance of age that they do not have. Those of the original system, which still exist on the island today, are heated either by hot air or by the sun. The hot-air estufas are stone buildings divided into compartments heated by pipes carrying air from one or more furnaces, and the new wine is kept in contact with the air of the estufa through a hole opened in the pipa (wine cask and measure, c. 400–500 litres). The air temperature in the estufa is kept between 60 and 70 °C, but it may fall to 54 °C, or even lower, in the case of good-quality wines.

The wines remain in the estufas for four to six months, in order to hasten their development and at the same time prevent them from fermenting. However, they almost always acquire a toasted taste, sometimes very pronounced, which the cellarman manages to reduce, though not to remove entirely, by subsequently using charcoal.

In sun estufas, the walls and roof of the building are made of glass.

In an establishment founded in 1889 by the late Count of Canavial, the wine, before going into the heating rooms (estâncias) or estufas (heated store for ageing Madeira wine), where it remains for weeks or months, enters a reservoir. From there it descends slowly through a tin pipe, in which it is heated in a bain-marie, sealed from the air, to a temperature of 70 to 80 degrees centigrade. It is at this temperature that the wine is received into the cask in which it goes to the heating rooms, where the temperature is 50 degrees. The temperature then falls slowly, with suitable pauses, until the end of the maturing process.

In this improved system the wine is sterilised by raising its temperature to 70 or 80 degrees. However, since this is the temperature at which the wine comes into contact with the air, it oxidises as a result and acquires a certain cooked taste.

This taste disappears almost entirely in another improved heating system, in which the wine is poured into a tank of alvenaria (local name for compact basalt used as building stone) that can be hermetically sealed and through which runs a coil carrying steam. The wine is drawn off only once it has cooled. The heating begins by raising the temperature to 80 degrees centigrade; fresh steam is then passed through the coil from time to time, so as to keep the wine at an almost constant temperature, or at varying temperatures, as required.

The system of improving wines in estufas, today much refined, had some detractors in former times. The preamble to the decree of 23 June 1834 states that it is ‘the principal cause of the present discredit of Madeiran wines, once highly esteemed’. Paulo Perestrelo da Câmara, however, defends the system in his Breve Noticia sobre a ilha da Madeira, and the decree of 20 February 1835 also considerably modified the doctrine of the earlier enactment regarding estufas.

There is no doubt that the estufas were much abused, and that by means of them many ordinary wines were prepared for sale in European markets at low prices, to the discredit of the fortified wines. Nevertheless, there were always good reasons not to abandon these establishments. If on the one hand they encouraged fraud, on the other they helped the honest merchant to raise the value of new wines from good grape varieties quickly, developing in them qualities that would otherwise have emerged only late.