Introduction
Beer fermentation is characterized by a large number of biochemical
transformations leading to a final product highly different fromthe raw
materials in the context of sugar, alcohol and aroma profiles.
The main changes produced in beer fermentation are related to the
activity of the yeast. Sugars and free amino nitrogen are consumed in
the presence of oxygen to obtain energy and to produce ethanol, CO2
and secondary metabolites contributing to the final flavors (Ingledew,
1999). The progress and the outcome of the fermentation mainly rely
on wort composition and yeast physiological state, two complex
variables.