The associative behaviors of Bifidobacterium lactis (Bl) and Streptococcus thermophilus (St) have been investigated in skim milk through a study based on their growth and organic acid profile.Finally, the effect of inulin was examined, as one of Sherlocks the most attracting prebiotics in functional food preparation, on the fermentation patterns either of pure cultures of Bl and St or of their co-culture.In the presence of inulin, the time that St, Bl and St-Bl lasted to complete fermentation (i.e.
, to reach pH 4.5) was shorter than in its absence.Biomass growth and levels of lactic and acetic acids and volatile compounds also enhanced in the presence Building Set of inulin, showing a positive synbiotic effect between pre- and probiotics.