Disclosed is a fermentation product which contains an equol-producing microorganism having a maintained equol-producing ability in a living state. In the production of a fermentation product by using an equol-producing microorganism and using a soybean powder or a soy milk as a raw material, (1) fermentation is carried out by using the equol-producing microorganism in the presence of a daidzein at pH 5.0 or higher under anaerobic conditions, thereby preparing a mother starter； (2) fermentation is carried out with the mother starter in the presence of a daidzein at pH 5.0 or higher, thereby preparing a bulk starter； and (3) fermentation is carried out with the bulk starter in a medium containing a soybean powder or a soy milk, thereby preparing a fermentation product.A In this manner, it becomes possible to produce a fermentation product which contains a microorganism having a maintained equol-producing ability in a living state.本發明之目的在於提供一種於活菌狀態下含有產生雌馬酚之微生物的發酵製品，且維持該產生雌馬酚之微生物的雌馬酚產生能力。使用產生雌馬酚之微生物並以大豆粉末或豆乳作為原料製造發酵物時，可藉由下述步驟來製造活菌狀態下含有維持雌馬酚產生能力之微生物的發酵物：(1)使用產生雌馬酚之微生物，在木質素黃酮(daidzein)類存在下，於pH5.0以上且厭氧條件下進行發酵以調製菌元(mother starter)；(2)使用前述菌元，在木質素黃酮類存在下，以pH5.0以上進行發酵，藉以調製大量菌元(bulk starter)；及(3)使用前述大量菌元，在含有大豆粉末或豆乳之培養基中進行發酵以調製發酵物。
