The effect of maltodextrin and xanthan gum on physicochemical, sensory and microbial properties of probiotic free-fat stirred-type yoghurt containing Lactobacillus paracasei subsp. paracasei

Nowadays yoghurt is the most popular fermented and probiotic dairy product in all over the world which is related to its unique properties and healthful values. The aim of this research was evaluate the effect of adding maltodextrin and xanthan gum singly and binary combination, on quality properties of the probiotic stirred yoghurt containing Lactobacillus paracasei subsp paracasei. Probiotic cell count, physicochemical and sensory properties of the samples were determined on 1st, 7th, 14th and 21st day of cold storage (4 ˚C). The results showed that the yoghurt containing combination maltodextrin and xanthan gum had the most alive probiotic cell count, best taste, texture, flavor and overall acceptability, the least syneresis and the most viscosity at the end of 21st day of storage. The lowest score of color and appearance belonged to control sample. In all samples pH, probiotic cell count and sensory properties were decreased during the storage, versus acidity, viscosity and syneresis were increased. Adding the compounds used to reduce syneresis and pH, and increase live probiotic cell count, acidity and improve the sensory properties of yoghurt samples in compare with control sample. In all samples(excluding control) , the probiotic cell count was more than 106 cfu/ml until the end of 21st day, shows the efficiency of using maltodextrin and xanthan gum in formulation of the probiotic yoghurt.