In: Chemistry
What processes typically occur during fermentation to prepare hard cider?
Fermentation of apple cider is the process by which yeast
converts the apple sugars into ethyl alcohol and carbon dioxide. It
occurs in two steps. First, yeast converts the sugar to alcohol and
then bacteria of lactic acid convert the natural malic acid into
carbon dioxide. This hard cider contains 2-3% solids and 2-8%
alcohol. Fermentation occurs in presence of these components such
as sulfur dioxide, yeast, sugar, and natural acids. Sulfur dioxide
is typically added to the freshly pressed juice before fermentation
is allowed to begin. It also has the effect of killing most of the
bacteria and yeasts present in the freshly squeezed
juice.