cryoextraction is the practice of extracting water from a liquid destined for fermentation to concentrate its sugars or from an alcoholic beverage to concentrate its alcohol. Winemakers in very cold climates such as Germany and Canada extract juice from frozen grapes to achieve higher sugar concentrations. In historical American applejack production, fermented cider could be partially frozen during winters; its water (solidified as ice) could be separated from its unfrozen alcohol. The resulting high-proof spirit was rich in (toxic) heads and tails and was known colloquially as skull-pop or Yankee antifreeze. The technique has deep historical roots, being practiced in Russia during the Middle Ages and China during the Eastern Han dynasty (25–220 ce). See heads and tails.
See also applejack and distillation, history.
Brook, Stephen. Liquid Gold: Dessert Wines of the World. Sag Harbor, NY: Beech Tree, 1987.
By: Doug Frost