Bread is a global staple food. Despite attempts to develop functional breads containing viable microorganisms, this has not been done yet because of the high temperature during baking. The aim of this study is to obtain synbiotic bread, hence hamburger bun and white pan bread were selected. Lactobacillus acidophilus LA-5 and L. casei 431 were encapsulated with calcium alginate and Hi-maize resistant starch via emulsion technique and coated with chitosan. The morphology and size of microcapsules were measured by scanning electron microscopy and particle size analyser. Inulin was added at 5% wheat flour mass basis for prebiotic effect. The encapsulated probiotics were inoculated into the bread dough and bread loaves were baked. The survival of encapsulated probiotics was determined after baking; also sensory evaluation was performed. Both types of bread met the standard criteria for probiotic products. The probiotic survival was higher in hamburger bun. L. casei 431 was more resistant to high temperature than L. acidophilus LA-5. A significant increase in probiotic survival was observed when the protective coating of chitosan was used in addition to calcium alginate and Hi-maize resistant starch. Storage for 4 days did not have any effect on the viability of encapsulated bacteria. The addition of encapsulated bacteria did not have any effect on flavour and texture; however, 5% inulin improved the texture of bread significantly. Results show that microencapsulation used in the production of synbiotic bread can enhance the viability and thermal resistance of the probiotic bacteria.
Keywords: alginate; bread; chitosan; inulin; microencapsulation; probiotic.