The probiotic bacteria must be viable to affect the health, but the non-viable bacteria could also affect the immunological status of the host. It is believed that the arrival of probiotic bacteria with food to different parts of intestine can increase probiotic bacteria adherence and the rate of colonization. Food products may contain many forms of probiotic bacteria, including culture concentrate that is added to a food (dried or deep-freeze form), the fermented or non-fermented food products, and dietary supplements in the form of drug products-powder, capsules or tablet. It is estimated that probiotic foods comprise between 60 and 70% of the total functional food market
