It is an object of the present invention to provide a method for producing fermented milk by promoting fermentation without adding any fermentation-promoting substance, and to provide novel fermented milk with a thick and smooth mouth feel and a mild flavor which has not been obtained conventionally and additionally with a hard texture not degrading during distribution state, as obtained by the method. As a consequence of investigations, it is found out that fermentation efficiency can be promoted by reducing the dissolved oxygen in a mix of raw materials for fermented milk at the start of fermentation through substitution with inert gases. It is also found out that the method including fermentation at general temperature in the above condition can shorten fermentation time to improve productivity, and that the method including fermentation at a fermentation temperature lower than a usual method for general fermentation time can produce novel fermented milk with a thicker and smoother mouth feel and a milder flavor than the mild flavor of fermented milk obtained by conventional low-temperature fermentation for a long period and with a hard texture never degrading during distribution stage, which has not been obtained conventionally, in addition that the fermented milk is obtained by the above method. As a consequence, the invention has been achieved.
