Microencapsulation of Lactobacillus acidophilus 5 with isomalto-oligosaccharide

Abstract

Co-extrusion microencapsulation of Lactobacillus acidophilus 5 (La-5) was performed using isomalto-oligosaccharide (IMO) as prebiotic, alginate as shell material and chitosan as the coating. The optimization of alginate (1.3% (w/v) to 1.7% (w/v) and IMO concentration (1.0% (w/v) to 5.0% (w/v) was evaluated based on bead size and microencapsulation efficiency of La-5. Subsequently, the chitosan-coated alginate with or without IMO were subjected to sequential digestion. It is found that 3.0% (w/v) IMO and 1.5% (w/v) alginate were the optimal concentration based on microencapsulation efficiency (MEE). The morphology of the beads containing IMO was found to be smooth and spherical, with diameter of 622.00 μm. The addition of IMO and chitosan are effective in protecting La-5 under gastric conditions but not effective in protecting the viability of La-5 under intestinal digestion.