Method of producing succinic acid-rich yeast which contains a higher concentration than conventional succinic acid, succinic acid-rich yeast, and provides a succinic acid-rich yeast extract. That is, the present invention relates to a method for producing a yeast extract, which is characterized in that the yeast is cultured under conditions that KLa (volumetric oxygen transfer coefficient) is 0.9~195hr -1, extracting the yeast extract by autolysis the one that performs the self-digestion in conditions that are 30~55 ℃ the temperature of the self-digestion solution method of manufacturing the yeast extract according to the above is a yeast that the yeast were grown in conditions respiratory quotient is 1.3 or more according to the yeast extract succinic acid content of 3.0 to 30.0 wt% per dry weight and is produced by the method for producing a yeast extract according to any one of the above method for producing a yeast extract according crab.コハク酸を従来よりも高濃度に含有するコハク酸高含有酵母の製造方法、コハク酸高含有酵母、及びコハク酸高含有酵母エキスを提供する。すなわち、本発明は、KLa(酸素移動容量係数)が0.9~195hr-1となる条件で培養された酵母から、自己消化により酵母エキスを抽出することを特徴とする酵母エキスの製造方法;前記酵母が、呼吸商が1.3以上である条件で増殖させた酵母である前記記載の酵母エキスの製造方法;自己消化液の温度が30~55℃である条件で自己消化を行う前記いずれかに記載の酵母エキスの製造方法;前記いずれかに記載の酵母エキスの製造方法により製造され、かつコハク酸含有量が乾燥重量当たり3.0~30.0重量%である酵母エキスに係る。
