Answer:
Yeast
Explanation:
Yeast is one single-celled microorganism that plays an important role in the process of fermentation. Yeast consumes the malt sugars and uses them to convert and exhume carbon dioxide and ethanol. This is why yeast is mainly used in the creation of beer. It also has secondary metabolites which greatly influence the final flavor of beer due to the many variations that can be created during the fermentation process.
