The stalk (3 to 5 percent of total weight)
Each bunch has a stalk that is discarted at the beginning of the wine making process.
The skin (6 to 10 percent)
The skins or peels of grapes contain coloring substances, as well as tannins and yeasts, which enable the juice to ferment. Red wines are made from dark-skinned grapes. White wines usually derive from light-skinned grapes, but they can also be made from dark varieties if the skins are separated immediately from the pulp after pressing.
The pulp (82 to 90 percent)
The pulpy interior of the grape, source of its juice, consists of water,sugars, acids, mineral substances and vitamins.
The seeds (2 to 4 percent)
These are rich in tannins and oils.
he fruit of the vine is the grape,which grows in bunches of varying size, consistency and color. The grape has four essential parts: