Application of biomacromolecules encapsulation systems for the long-term storage of Lactobacillus plantarum F1 and Lactobacillus reuteri 182.

The aim of this study was to improve the viability of lactic acid bacteria (LAB) during extended storage of 1 year and mechanical characteristics of the calcium alginate beads with co-encapsulation of prebiotics and chitosan coating and subsequent freeze drying. The results revealed that the addition of trehalose to alginate matrix effectively protects the LAB cells during freeze drying, i.e., the survival rate has increased up to more than 92.5 %. Chitosan coating reinforced Ca-alginate beads, therefore the sphericity and mechanical strength of the beads improved. The findings also showed that bacteria encapsulation with the prebiotics resulted in more cells stability during the prolonged storage of 1 year and were 4.82 ± 0.06 log CFU g-1 in the lyophilized alginate-trehalose beads for Lactobacillus plantarum and 5.64 ± 0.08 log CFU g-1 in the lyophilized alginate-trehalose-inulin beads for Lactobacillus reuteri. No survival, however, was noted for the LAB cells in wet capsules after the same period. This study demonstrated that prebiotics had a significant impact on the viability of cells during freeze drying and storage. What is more, physical properties of the alginate beads were enhanced by coating beads with the chitosan.

W/O/W double emulsion-loaded alginate capsules containing Lactobacillus plantarum and lipophilic sea buckthorn (Hippophae rhamnoides L.) pomace extract in different phases.

In this study, double emulsion containing L. plantarum F1 cells and prebiotic mannitol in the inner water phase, lipophilic sea buckthorn pomace extract as an antioxidant in the oil phase, and alginate in the outer water phase showed high encapsulation yield (82.19%), good cell survival rate (76.99%) and low chemical degradation of the oil (peroxide value - 3.8 meq O2/kg fat) after 42 days of storage. Gelation of the outer water phase enhanced the viability of L. plantarum F1 cells both during storage and under gastrointestinal conditions due to strong physical barrier formation. Encapsulated L. plantarum F1 viability throughout the 30-day storage period decreased to the value meeting the minimum required dose for probiotics. In vitro digestion of the loaded alginate capsules showed high survival rate of encapsulated cells under gastric conditions and significant reduction at the end of the duodenal phase of digestion.