Selective enumeration of probiotic bacteria in food and food supplements

Probiotics are defined as live microorganisms which when consumed in adequate amounts, confer a health benefit on the host. They represent a fast developing field, which in past years has expanded from the traditional health benefit areas of digestive comfort and immune protection. Bifidobacteria and lactobacilli are most frequent used probiotic organisms. Bifidobacteria exert numerous positive effects on human health such as protection against infectious diarrhea, help to create a stable microbiota in preterm infants, alleviation of lactose maldigestion, lowering of serum cholesterol, prevention of infection by pathogenic bacteria and anti-carcinogenic capabilities. Similar effects were also found in lactobacilli. Due to the commercial use of these microorganisms is requirement for their selective quantitative control in probiotic products. According to the international ISO / IDF standards, however, there is currently only a procedure for the selective determination of the genus Bifidobacterium and species of Lactobacillus acidophilus. New selective media will be developed according to bacteria substrate preferences (phenotypic profiles). These media for enumeration by culture methods will be available for more exact analysis of the probiotic microorganisms in commercial products