The invention relates to a process for the production of at least one microbial metabolite having at least 3 carbon atoms or at least 2 carbon atoms and at least 1 nitrogen atom by means of sugar-based microbial fermentation, comprising: a) the preparation of a sugar-containing liquid medium with a monosaccharide content of more than 20% by weight from a starch feedstock, the sugar-containing liquid medium also comprising non-starchy solid constituents of the starch feedstock; b) the fermentation of the sugar-containing liquid medium for the production of the metabolite(s); and c) depletion or isolation of at least one metabolite from the fermentation liquor, wherein a microorganism strain which produces the desired metabolite(s) is cultivated with the sugar-containing liquid medium, said liquid medium being obtained by: a1) milling the starch feedstock; and a2) liquefying the millbase in an aqueous liquid in the presence of at least one starch-liquefying enzyme, followed by saccharification using at least one saccharifying enzyme, where at least some of the millbase is liquefied by continuous or batchwise addition to the aqueous liquid.