After harvesting, the grapes are crushed to release the must (grape juice). Crushing simply means to break the berries skin, allowing juice and pulp to be exposed and the yeast to start fermenting.
Maceration is the phase of phenolic (tannin, color and flavor) extraction. Temperature Controlled Maceration (Cold Soaking) delays fermentation, allows a longer contact juice - crushed grapes and results in more intense wines.
A thick layer of skins, called the cap floats to the top. If left undisturbed, the extraction does not take place. The cap must be mixed with the juice through 2 techniques: Punching Down and Pumping Over.
Alcoholic Fermentation is the transformation of grape juice into wine, of sugar into alcohol.
Sugar+Yeast+Heat = Alcohol+CO2+Flavors
Fermentation in stainless steel does not add ekstra aromatic compounds (neutral vessel). Fermentation in oak barrels adds Secondary flavors.
Alcoholic Fermentation creates heat. Red wines are fermented at higher temperatures (20-32°C, 68-90°F) to extract color and tannins. Rosé and white wines are fermented at lower temperatures (12-22°C, 54-72°F) to maximize the fresh fruit aromas.
Pressing separates the liquid from the solid. White wines are pressed immediately to avoid contact with skins, stems and seeds rich in tannins, while red wines are pressed much later in the vinification process. This is the major difference between white and red wines.
Maturation refers to a period of time after Fermentation and before Bottling. Blending, MLF, clarification and stabilization happen during this phase.
The wine is exposed to air while in oak barrels and flavors and color change. Some grape-derived aromas fade and oak flavors of vanilla, cedar, smoke appear. The color purple and violet progressively transforms into brick and orange.
Aging refers to the changes in wine after bottling.
The astringent and harsh mouth feeling of tannins progressively is replaced by a smoother and rounder one.