Autovinification

autovinification, method of vinification designed to extract maximum colour from red grapes and used primarily in the production of red port. Autovinification, a process involving automatic pumping over, was developed in algeria in the 1960s, where it was known as the Ducellier system. Faced with a shortage of labour in the 1960s, port producers were forced to abandon the traditional practice of treading grapes by foot in lagares. Many isolated quintas had no electricity and so shippers built central wineries. The power supply was erratic and too weak for sophisticated pumps or presses so the shippers installed autovinification tanks in order to extract sufficient colour and tannins in the short fermentation period prior to fortification. Autovinification is a self-perpetuating process induced by the build-up of pressure; no external power source is needed.