Chitosan coated skim milk-alginate microspheres for better survival of probiotics during gastrointestinal transit

Microencapsulation of probiotic cells is now under special attention because it is considered as the best method for improving the survivability of probiotics. In the present study, alginate, alginate-skim milk and chitosan coated alginate-skim milk coated microspheres of probiotics such as L.rhamnosus and L.plantarum were prepared. The encapsulating efficiency was found to be above 96% for L.plantarum and above 98% for L.rhamnosus. The skim milk was found to be a better matrix for encapsulation and chitosan coating, making the microspheres stronger compared to uncoated microspheres. The stability study of encapsulated and non-encapsulated probiotic was done for a month. The tolerance of encapsulated probiotics in artificial gastric fluid and release profile of probiotic in simulated intestinal fluid was also studied. This is the first study where chitosan coated alginate-skim milk was used for probiotic encapsulation and suggests promising encapsulating/enfolding material for improving the probiotics survivability.