Meanwhile, it has been numerously reported that other inhibitory substances may contribute to the antimicrobial activity as well (Niku-Paavola et al., 1999, Servin, 2004 and Valerio et al., 2004), and only a few authors suggest that the production of organic acids is the sole factor responsible for the antimicrobial activity of lactobacilli (Ogawa et al. 2001).