The invention relates to a preparation of metabolically active bacteria,compositions comprising such a preparation, e.g. probiotic supplements oranimal feeds, and to uses thereof, for example in the treatment of diseasesaffecting the intestinal microbial balance. Also described are a growthsubstrate for microorganisms comprising a mixture of complex and simple sugarsand a process for the manufacture of preparations of metabolically activemicroorganisms using this growth substrate.
