Yeast
Yeast
Yeast in wine is a microscopic, single celled fungus, typically Saccharomyces cerevisiae, which triggers fermentation by transforming the sugars in must into ethanol and carbon dioxide. Yeasts are essential for converting grape juice into wine and they determine its final alcohol content, aroma and flavor profile. They can be wild yeasts, naturally present in vineyards, on grape skins and in wineries; or cultured yeasts, which are specifically grown in the lab.
See Also
Amphora
Amphora is a traditional clay or terracotta vessel used for fermenting, aging and storing wine. These vessels are neutral and porous, allowing micro oxygenation without adding oak flavors.
Oxidation
Oxidation is a chemical reaction that occurs when oxygen in the air comes in contact with the alcohol in wine, converting ethanol into acetaldehyde, then acetic acid. It causes wines to lose their vibrant colors and reduces fresh fruit aromas.
Oak
Oak imparts flavor, aroma and texture into wines through fermentation in oak barrels. These barrels act as gentle, breathable vessels that add complex notes and improve the wine's overall structure and mouthfeel.
Hybrid
Hybrid varieties are created by crossing two or more different grapevine species to get a final product that offers resistance to cold, diseases and humidity, making them ideal for tough climates.
Must
Grape must is the freshly pressed, unfermented grape juice which contains the fruit's skins, seeds and sometimes stems (collectively referred to as pomace).
Harvest
The harvest marks the end of the vine growing cycle, typically occuring between August and October in the Northern hemisphere. It is the stage where ripe grapes are picked from the vineyard to begin winemaking.
Saccharomyces Cerevisiae
Saccharomyces Cerevisiae is the major yeast species involved in wine fermentation. Also known as "wine yeast" or "baker's yeast", it converts the sugar in grape juice to ethanol and carbon dioxide, creating wine.
Anthocyanins
Anthocyanins are natural polyphenol pigments located in the red grape skins, responsible for the red, purple and blue colors in young red wines. They determine the wine's hue, shifting from vibrant red to brownish orange as they age.