Aspergillus plays lub luag haujlwm tseem ceeb hauv kev tsim cov sorghum cawv. Nws lub luag haujlwm tseem ceeb yog hloov cov hmoov txhuv nplej siab rau hauv qab zib, thiab tom qab ntawd rau hauv cawv, yog li ua tiav fermentation. Tsis tas li ntawd, Aspergillus tuaj yeem rhuav tshem cov protein thiab cov rog, tsim cov amino acids dawb thiab cov tshuaj tsw qab, uas cuam tshuam rau aroma thiab saj ntawm cawv.
Txawm li cas los xij, "koji tsw" kuj yog ib qho teeb meem tshwm sim hauv sorghum cawv ntau lawm. Koji tsw yog hais txog cov kua qaub, pwm, lossis tsis tiav fermented saj hauv cawv. Koji tsw ntau dhau yuav ua rau lub saj tsis zoo thiab cuam tshuam rau qhov zoo ntawm cawv. Yog li ntawd, tswj koji tsw yog qhov tseem ceeb tshwj xeeb.
