What components are produced by Kōji mould?

The correct choice highlights the diverse range of components that kōji mould produces, which are essential for the sake brewing process. Kōji mould, specifically Aspergillus oryzae, plays a critical role in converting starches from rice into sugars through the action of amylase enzymes. These sugars are subsequently fermented by yeast to produce alcohol. Additionally, the mould generates amino acids and peptides that contribute to the umami flavor profile of sake, enhancing its complexity. Vitamins produced during this process can also improve the overall nutritional profile of the sake.

In contrast, other choices refer to components not produced directly by kōji mould. The fermentation process itself involves yeast and can result in alcohol and carbon dioxide production, but these are primarily the result of yeast activity rather than the direct output of kōji. Furthermore, tannins are more commonly associated with wine rather than sake. Lastly, while proteins, acids, and carbohydrates play a role in the sake-making process, the specific components generated by kōji mould do not align with that choice. Therefore, the first choice accurately captures the important outputs derived from the fermentation and enzymatic activities of kōji mould.