Survival and stability of free and encapsulated probiotic bacteria under simulated gastrointestinal conditions and in pasteurized grape juice

Abstract

The present study was designed to explicate the effect of encapsulation on the stability of Bifidobacterium bifidum in pasteurized grape juice and in vitro gastrointestinal conditions. Purposely, hydrogel beads were prepared using sodium alginate and K-carrageenan by internal gelation method. Free and encapsulated probiotics were incorporated in pasteurized grape juice samples. The initial count in grape juice samples with free probiotic cells was calculated as 9.35 log cfu/mL that reduced to 6.58 log cfu/mL after 35 days. Likewise, the probiotic count, that is, in samples containing encapsulated probiotics reduced to a level of 8.51 log cfu/mL and 7.09 log cfu/mL after the mentioned storage period. The number of free viable cells in juice samples was lower than (107 cfu/g) the minimum recommend level. Similarly, the free cells showed a poor survival under simulated gastrointestinal conditions. Furthermore, encapsulation affected the physicochemical (pH, acidity, and Brix) and sensorial characteristics of the juice samples. Practical applications The probiotic delivery through carrier food and under hostile gastrointestinal conditions is a great challenge due to their low survival. The encapsulation technology can be used to protect the target delivery of probiotics. The encapsulation technology is a useful tool for delivering the probiotics for both dairy and nondairy food matrices. Encapsulation also ensures the recommended therapeutic level (1107–108 cfu) during transit and storage.