There is provided a method for recovering spent grain, comprising the steps of: a) adding a batch of mixed solution of a batch of spent grain and a first fermenting composition to a second fermenting composition; b) mixing the added batch of mixed solution with the second fermenting composition, whereby a fermented mixture is obtained; and c) separating the fermented mixture into a liquid product and a solid product; wherein the liquid product and the solid product have a prolonged durability compared to the durability of the batch of spent grain when mixed solution has been added in step a). An advantage of the inventive method is that by-products such as spent grain are efficiently turned into valuable products.