Disclosed is a method for producing a fermented food/beverage, which comprisesadding a lactic acid bacterium strain belonging to Lactobacillus brevis to aculture medium containing a plant-derived raw material in an amount of 50 mass%or more in terms of undiluted content and malic acid in an amount of 0.2 to 2.0 mass%of malic acid or 2.0 to 20.0 mass% of fructose and having a pH adjusted to 5.0 to 7.0,and conducting the fermentation until at least the end of the exponential growthphase of the lactic acid bacterium strain. In the method, an acid or a lactic acid-producingbacterium strain is further added to the culture medium at any point of time lyingbetween the initiation of the fermentation to the end of the exponential growthphase. The fermentation is carried out in such a manner that the pH of the culturemedium is decreased at a rate of 0.01 to 0.3 (l/hr) during a period between the initiationof the fermentation to the end of the exponential growth phase and becomes 3.3to 4.6 when the fermentation is completed.
