Comparison of molecular techniques with other methods for identification and enumeration of probiotics in fermented milk products.

Nowadays, an increasing attention is being given to fermented milk products including yogurt, kefir, buttermilk, and acidophilus milk. Fermented milks, especially the ones containing probiotics, are claimed to be useful for health of host (such as intestinal- and immune-associated diseases). Their healthful effects could be significantly enhanced by incorporating probiotic microorganisms; those have healthful advantages for host when consumed in an appropriate viable number in food products. Probiotic dairy products have stepped to the market and are being commercially produced under various brand names. In addition, these products are legislatively obliged to be labeled for the microorganisms contained. Therefore, identification and enumeration of their microorganisms are a cause of concern. Several culture-dependent methods have been introduced and used to identify the microorganisms, in which the researchers have experienced multiple difficulties. Thereby, molecular approaches were present as an alternative, offering advantages such as accuracy, sensitivity, specificity, and speed. This article reviews the molecular approaches employed for identification and enumeration of probiotics in fermented milk products.