In order for a potential probiotic strain to be able to exert its beneficial effects, it is expected to exhibit certain desirable properties. The ones currently determined by in vitro tests are
(i) acid and bile tolerance which seems to be crucial for oral administration,
(ii) adhesion to mucosal and epithelial surfaces, an important property for successful immune modulation, competitive exclusion of pathogens, as well as prevention of pathogen adhesion and colonisation,
(iii) antimicrobial activity against pathogenic bacteria,
(iv) bile salt hydrolase activity.