Metabolism of Saccharomyces cerevisiae

Saccharomyces cerevisiae, commonly known as brewer's yeast, is essential in baking and the production of alcoholic beverages such as beer and wine. This yeast plays a crucial role in fermentation, a metabolic process that turns sugars into alcohol, carbon dioxide and other substances that contribute to the flavor and texture of finished products.

The metabolism of Saccharomyces cerevisiae can be divided into two main phases:

1. Aerobic Phase (Breathing) :

   • When oxygen is available, yeast uses aerobic respiration to convert sugars into energy (ATP), water and carbon dioxide.
   • This process produces a large amount of energy, which is vital for the growth and multiplication of the yeast.

2. Anaerobic Phase (Fermentation) :

   • In the absence of oxygen, the yeast switches to alcoholic fermentation. Sugars are mainly converted into ethanol and carbon dioxide.
   • This process is less energy efficient than aerobic respiration, but is essential for the production of alcohol and for the leavening of bread dough.

Yeast not only helps dough rise through the production of carbon dioxide, but also contributes to the flavor and structure of bread through the production of alcohols and other volatile compounds during fermentation. Accurate management of the fermentation process is essential to guarantee the quality and desired characteristics of the finished product, be it bread, pizza, focaccia or alcoholic beverages.