Effect of using different probiotic cultures on properties of Torba (strained) yoghurt

Probiotic foods are defined as “foods containing live microorganisms, which actively enhance health of consumers by improving the balance of microflora in the gut when ingested live in sufficient numbers” (Fuller, 1992; Shah, 2004). In terms of the growth and viability of probiotic bacteria in retail products, fermented milks are excellent vehicles for the transfer of selected strains to humans (Itsaranuwat et al., 2003). Dairy products containing probiotic cultures such as Bifidobacterium sp. and Lactobacillus sp. have been produced around the world for many years and it is estimated that currently more than 80 products containing these bacteria are being produced worldwide (Maity et al., 2008). Among these products the most widely encountered one is yoghurt. The probiotic bacteria can be incorporated into yoghurt by using different methods. They may be inoculated together with the yoghurt culture prior to fermentation process, or alternatively, added to the yoghurt after fermentation is completed (GilliSummary