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

The viability of Lactobacillus casei LAFTI (R) L26, Bifidobacterium animalis subsp. lactis LAFTI (R) B94 and Lactobacillus acidophilus LAFTI (R) L10, their proteolytic activities and effects on chemical, textural and sensory properties of Torba yoghurts were assessed during 14 days of storage at 4 degrees C. These probiotic cultures were separately added after the fermentation of milk with yoghurt culture but prior to packaging of the product. Probiotic bacteria reached the recommended level of 6 log cfu/g in Torba yoghurt except B. animalis subsp. lactis B94. The addition of probiotic bacteria resulted in an appreciable proteolytic activity but also textural defects due to the lower total solid content in the final product.