Abstract: The present invention relates to a biocatalytic process for producing an aroma substance or a mixture of aroma substances, comprising the steps of: providing a conversion medium comprising a plant component of the gooseber-ry family, the rose family and/or the grapevine family; contacting the conversion medium with at least one fungus from the division of stander fungi capable of forming an aroma substance or a mixture of aroma sub-stances on the conversion medium; converting the plant component to the aroma substance or mixture of aroma substances with the aid of the fungus; and optionally recovering the aroma substance or mixture of aroma substances, wherein the aroma substance or mixture of aroma substances preferably com-prises at least one compound selected from the group consisting of 2-octanone, 2-nonanone, 2-undecanone, linalool oxides, benzaldehyde, geraniol, 2-octanol, methylanthranilate, 2-aminobenzaldehyde and linalool.