Assessing the survival of Lactobacillus casei in probioticchocolate during 6 months in ambientandrefrigerated temperatures

Nowadays, regarding to human need to functional and probiotic foods and the extend use of these foods, considerable attention is donated to production and development of probiotic products which eventually can play an important role in improvement of society health.Additionally, investigations have identified the chocolate as a proper carrier for probiotics. In the present study,probiotic chocolate containing Lactobacillus casei was manufactured and then some of physicochemical parameters including pH and water activity (aw) together with survival assessment of Lactobacilluscasei in chocolate were investigated.Addition of Lactobacillus casei to chocolate haven’t had any adverse and significant effects on physicochemical parameters such as pH and water activity during 6-month storage time at ambient and refrigerated temperatures (P>0.05). According to obtained results, the amount of water activity in probiotic chocolate was higher than control chocolate (P0.05).The obtained results declared that the enriched chocolate with Lactobacillus casei can be stored at ambient temperature without having any unfavorable changes in its physicochemical properties such as pH and water activity. Also, even with slight decrease in population of probiotic bacteria of Lactobacillus casei during the 6-month storage time at temperatures of 4 and 22 ˚C, but the final product which included 108 CFU/g probiotic cells can be considered as a functional probiotic foodstuff.