Investigation of physicochemical and sensory properties of probiotic Chavil yogurt containing microencapsulated Lactobacillus acidophilus (PTCC 1643) with sodium alginate and Arabic gum

Nowadays, the consumption of probiotic products is increasing. Adding probiotic bacteria to traditional products is one of the ways to create attraction in the consumption of these products. On the other hand, the survivability of probiotics during the process and storage time is one of the obstacles to expand the use of these products. With this aim, microencapsulated Lactobacillus acidophilus(bead) was produced with sodium alginate and Arabic gum (in 4 concentrations 0.2, 0.4, 0.6, and 0.8%). The produced beads were spherical in shape (aspect ratio 1.06) and had high microencapsulation efficiency (90.52+2.02%). With the increase in the concentration of Arabic gum, the diameter of the outer layer of the beads increased. Since the survivability of the beads containing Arabic gum (0.8%) was 2.47 log CFU.ml-1 in 6 minutes; therefore, this bead was chosen for adding to Chavil yogurt. The survival rate of probiotic bacteria was estimated to be 19.31% and 50.60% in the yogurt sample containing free bacteria and beads separately at the end of the storage period. In the simulation gastrointestinal condition, the survival percentages were 40.9% and 6.95% for free bacteria and bead separately. Chavil yogurt containing beads had the lowest score in the sensory components containing odor, flavor and color, although it had the highest score in the texture parameter. Therefore, the use of double-layer beads containing sodium alginate and Arabic gum may be recommended.