PROBLEM TO BE SOLVED: To provide a method for producing a kokumi-imparting substance-containing yeast that highly contains at least one of γ-Glu-Abu and γ-Glu-Abu-Gly, and a method for producing a kokumi-imparting substance-containing yeast extract. SOLUTION: A yeast proliferating step of culturing yeast which is modified to reduce intracellular acetolactate synthase activity and isoleucine- and valine-requiring yeast in a medium containing isoleucine and valine, and a step of growing the same. When the content of isoleucine is less than 0.2% by mass, valine is added to the medium to cultivate the yeast, and a kokumi-imparting substance producing step of producing a kokumi-imparting substance is included. Is a method for producing a yeast containing a richness imparting substance, which is at least one of γ-Glu-Abu and γ-Glu-Abu-Gly. [Selection diagram] None【課題】γ－Ｇｌｕ－Ａｂｕ及びγ－Ｇｌｕ－Ａｂｕ－Ｇｌｙの少なくともいずれかを高含有するコク味付与物質含有酵母の製造方法及びコク味付与物質含有酵母エキスの製造方法を提供する。【解決手段】細胞内のアセト乳酸シンターゼ活性が低下するように改変され、イソロイシン及びバリン要求性の酵母を、イソロイシン及びバリンを含有する培地で培養し、増殖させる酵母増殖工程と、前記培地中のイソロイシンの含有量が０．２質量％未満のときに、バリンを前記培地に加えて前記酵母を培養し、コク味付与物質を生成させるコク味付与物質生成工程とを含み、前記コク味付与物質が、γ－Ｇｌｕ－Ａｂｕ及びγ－Ｇｌｕ－Ａｂｕ－Ｇｌｙの少なくともいずれかであるコク味付与物質含有酵母の製造方法である。【選択図】なし
