Only yeast is added to the fermentation of fruit wine, not koji.

There is mold inside the koji, which is used in the fermentation process of liquor. Its main function is to convert starch into sugar.

The role of yeast in the fermentation process of fruit wine is to convert sugar into alcohol.

Fruit is mainly sugar and contains almost no starch.

You can give it a try by adding yeast. After the fermentation is completed, if the musty smell is strong, it is recommended to use distillation to distill the wine and drink it as XO.