PROBLEM TO BE SOLVED: To provide a new and useful method for breeding HEMF-hyper-producing microorganisms by clarifying HEMF production-relevant genes in yeast, and also provide an HEMF production method and a method for producing fermented food of higher HEMF content in a simple manner not much different from the conventional fermented food production process.SOLUTION: Provided is a HEMF production method utilizing an yeast being deficient in ADH1 gene function. Also provided is a method for producing fermented food of high HEMF content characterized in that the yeast being deficient in ADH1 function is added during the initial to middle stage of fermentation process in the manufacturing process of fermented food.【課題】酵母におけるHEMF生成関連遺伝子を明らかにし、HEMF高生産微生物の育種に対する新規かつ有用な製法を与えるのと共に、通常の発酵食品の製造工程と大きく変わらない方法で、簡便にHEMFの含有量を増加せしめることが可能となるようなHEMFの製造法及びHEMF高含有発酵食品の製造方法を確立する。【解決手段】ADH1遺伝子の機能を欠損した酵母を用いることを特徴とするHEMFの製造法、及び発酵食品製造工程の発酵開始時~発酵中期に、ADH1遺伝子の機能を欠損した酵母を添加することを特徴とするHEMF高含有発酵食品の製造方法。【選択図】なし