Background: Probiotic milk products with valuable nutritional and health properties is one the most important issues of nutrition and medicine. The aim of present study was to produce chocolate milk containing microencapsulated probiotic bacteria.

Materials and methods: In the present study, the Lactobacillus casei and Bifidobacterium animalis were injected into chocolate milk both in free and microencapsulated forms. Sodium alginate and resistant starch were used for microencapsulation via extrusion method. The changes in probiotic bacteria count and their sensory acceptability were evaluated at 5°C for 21 days. Also, survival rate of bacteria was determined in simulated gastrointestinal conditions.

Results: The significant survival rates of microencapsulated bacteria was observed in chocolate milk and also in simulated gastrointestinal condition in all conditions (p<0.05).

Conclusion: Based on the sensory physicochemical evaluations, the chocolate milk can be produced containing microencapsulated Lactobacillus casei and Bifidobacterium animalis with expiration time of 6 and 9 days, respectively. Given the important role of such products in disease prevention and boosting the immune system, so the use of them is recommended in time of war.