The fermented juice is called cider in England but is known as hard cider in the United States. In Europe, fermented apple juice is known as cider (France), sidre (Italy), sidra (Spain), or applewein (Germany and Switzerland) where the name for the corresponding unfermented product is clearly distinguished as apple juice.
Ciders are made by fermenting the juice of apples, often with some added pear juice. The juice may be either fresh or reconstituted from concentrate. In England, France, and Spain, most cider is produced from the juice of special cultivars of cider apples, referred to as bittersweet, bitter-sharp, sweet, or sharp, depending on the relative levels of tannins and acids.
The tannins in cider change significantly during fermentation; for instance, chlorogenic, caffeic, and p-coumaryl quinic acids are reduced with the formation of dihydroshikimic acid and ethyl catechol.
Cider with higher alcohol content is usually dry, whereas the one with a lower content is naturally sweet, due to the presence of residual sugars (soft cider: 1–5% ABV; strong cider is above 5–8% ABV).
Although juice from any apple can be made into cider, the cider makers suggest that apple should have certain characteristics: relatively high sugar content for alcohol production, a fibrous tissue to facilitate juice extraction, tannin to provide a bitter or astringent taste and a pleasant apple taste and aroma.
According to European Cider and Fruit Wine Association, apples for cider are classified into four broad categories: sour, bitter sour, bittersweet and sweet. The main criteria for the classification of apples are their acidity, which gives the astringent flavor, phenolic compounds, which impart the bitter taste and sugar content, which determines the alcoholic concentration of cider.
Apple cider
