Fecha de publicación: 28/12/2021 Fuente: Wipo Tobacco Agriculture The invention relates to a mixed tobacco fermentation method. The method comprises the following steps of respectively inoculating bacillus subtilis and phaffia rhodozyma on an LB agar culture medium and a YPD agar culture medium, respectively culturing for 24 hours at 37 DEG C and culturing for 5-7 days at 22 DEG C to obtain single colonies of the bacillus subtilis and the phaffia rhodozyma; respectively inoculating the single colonies into an LB liquid culture medium and a YPD liquid culture medium, respectively culturing for 20 hours at 37 DEG C and culturing for 28-29 hours at 22 DEG C to obtain a bacillus subtilis seed solution and a phaffia rhodozyma seed solution, and mixing the bacillus subtilis seed solution and the phaffia rhodozyma seed solution in an isopyknic manner to obtain a mixed bacterium solution; centrifuging the mixed bacterial liquid, collecting thalli and washing; resuspending the washed thalli to obtain a bacterial suspension; and adding the bacterial suspension and rhizopus powder into tobacco leaves, and fermenting at 25 DEG C for 7-10 days. By means of the method, the bacillus subtilis, the phaffia rhodozyma and the rhizopus are compounded and mixed, so that macromolecules such as starch and protein which have negative effects on the quality of the tobacco leaves can be degraded into alcohols, lipids, aldehydes and aroma small molecular substances, and the quality of the tobacco leaves is effectively improved.