jästgärning

Jästgärning, often translated as yeast fermentation, is a metabolic process that converts sugar into alcohol and carbon dioxide in the absence of oxygen. This process is carried out by various species of yeast, particularly those belonging to the *Saccharomyces* genus. Yeastgärning is fundamental to the production of numerous food and beverage products, including bread, beer, wine, and spirits.

In the context of baking, yeastgärning causes dough to rise. Yeast consumes sugars present in the flour and produces carbon dioxide gas, which creates bubbles within the dough, leading to an increase in volume and a lighter texture in the final baked good.

In brewing and winemaking, yeastgärning is the primary mechanism for alcohol production. Yeast is introduced to a liquid containing fermentable sugars (such as malted barley for beer or grape juice for wine). The yeast then metabolizes these sugars, producing ethanol (alcohol) and carbon dioxide. The specific yeast strain used, temperature, and duration of fermentation all influence the final flavor profile and alcohol content of the beverage.

Historically, yeastgärning was a crucial process for food preservation, as the alcohol produced could inhibit the growth of spoilage microorganisms. It remains a vital industrial process worldwide, underpinning significant sectors of the food and beverage industry.