Addition of amino acids to fermentation media affects the growth and brewing profiles of yeast. In addition, retaining mitochondrial activity during fermentation is critical for the fermentation profiles of brewer’s yeasts. However, a concrete mechanism linking amino acids in fermentation media with mitochondrial activity during fermentation of brewer’s yeasts is yet unknown. Here, we report that amino acids in fermentation media, especially methionine (Met) and glycine (Gly), stabilize mitochondrial activity during fermentation of sake yeast. By utilizing atg32Δ mutant sake yeast, which shows deteriorated mitochondrial activity, we screened candidate amino acids that strengthened the mitochondrial activity of sake yeast during fermentation. We identified Met and Gly as candidate amino acids that fortify mitochondrial activity in sake yeast during fermentation. To confirm this biochemically, we measured reactive oxygen species (ROS) levels in sake yeast fermented with Met and Gly. Yeast cells supplemented with Met and Gly retained high ROS levels relative to the non-supplemented sake yeast. Moreover, Met-supplemented cells showed a metabolome distinct from that of non-supplemented cells. These results indicate that specific amino acids such as Met and Gly stabilize the mitochondrial activity of sake yeast during fermentation and thus manipulate brewing profiles of yeast.; Dodatak aminokiselina u fermentacijsku podlogu utječe na rast i aktivnost kvasca, a zadržavanje aktivnosti mitohondrija tijekom alkoholnog vrenja je kritično za aktivnost pivskog kvasca. Međutim, mehanizam djelovanja aminokiselina u fermentacijskoj podlozi i njihov utjecaj na aktivnost mitohondrija pivskog kvasca tijekom vrenja još uvijek nije poznat. U ovom radu smo utvrdili da aminokiseline u fermentacijskoj podlozi, osobito metionin i glicin, stabiliziraju aktivnost mitohondrija kvasca tijekom proizvodnje pića sake. Pomoću mutanta atg32△, koji ima narušenu aktivnost mitohondrija, istražili smo aminokiseline koje povećavaju aktivnost mitohondrija kvasca tijekom vrenja. Identificirali smo metionin i glicin kao aminokiseline koje bi mogle povećati aktivnost mitohondrija kvasca tijekom proizvodnje pića sake. Da bismo to potvrdili, izmjerili smo količinu reaktivnih oblika kisika u kvascu nakon vrenja u podlozi s metioninom i glicinom. Kvasac koji je fermentirao u podlozi s metioninom i glicinom zadržao je relativno veliku količinu reaktivnih oblika kisika u usporedbi s kvascem koji je fermentirao u podlozi bez dodatka aminokiselina.