The present invention relates to an activator for a lactic bacteria-based ferment, characterised in that it comprises at least: one reducing disaccharide, one non-reducing disaccharide, an alkaline metal salt and/or an alkaline earth metal salt. The invention also relates to the ferment which is activated by means of said activator. The present invention is also concerned with the process for preparing an industrial product or food product, characterised by the use of the activator.