Fermented food products containing probiotic strains, and their preparation process

A process for the preparation of a fermented food product from a starting substance, comprising the following successive stages:

• a stage of seeding of a starting substance, optionally pasteurized, by inoculation with seeding ferments containing 4·106 to 1·107 bifidobacteria per ml of starting substance, in order to obtain a seeded substance,
• a stage of fermentation of the seeded substance obtained in the preceding stage, such that the temperature at the start of fermentation is 36 to 38° C., the temperature at the end of fermentation is 37 to 9° C., and the fermentation time is 8 to 11 hours, in order to obtain a fermented substance,
• a stage of intermediate cooling of the fermented substance obtained in the preceding stage, such that the intermediate cooling time is 1 hour 30 minutes to 2 hours and the intermediate cooling temperature is 4 to 18° C., in order to obtain a pre-cooled substance,
• a stage of storage of the pre-cooled substance obtained in the preceding stage, such that the storage time is less than 15 hours, in order to obtain a stored substance,
• a stage of final cooling of the stored substance obtained in the preceding stage, such that the temperature at the start of the final cooling is less than 21° C. and the temperature at the end of the final cooling is 2 to 6° C., so as to obtain a fermented food product.