Facultative anaerobe

Facultative anaerobes are microorganisms that can grow both in the presence of oxygen and in its absence. Like yeast, these microbes play an important role in the fermentation process. In sake brewing in particular, facultative anaerobes produce lactic acid, which increases acidity and suppresses the growth of other microorganisms, and in this way they influence flavor and quality. Because they help shape the distinctive taste and aroma of sake, facultative anaerobes are regarded as highly important in brewing science.