Protection of probiotic microorganisms by microencapsulation

Probiotic bacteria are used in the production of fermented dairy foods, pharmaceutical products and health supplements. They play an important role in promoting and maintaining human health. In order, to produce health benefits probiotic strains should be present in a viable form at a suitable level during the product's shelf life until consumption and maintain high viability throughout the gastrointestinal tract. Despite the importance of these beneficial microorganisms many investigations have shown their poor viability and stability, especially for bifidobacteria in fermented products. The introduction of microencapsulation techniques for protection of probiotic strains has resulted in greatly enhanced viability of these microorganisms in food products as well as in the gastrointestinal tract. This paper gives an overview of available microencapsulation techniques and materials for probiotic protection and stabilization. Several methods of microencapsulation for probiotic bacteria, including extrusion, emulsification, drying (fluidized bed, spray, freeze) and spray coating techniques, are presented. The commonly used supporting materials like alginate, starch, chitosan, gelatin, waxes, biogums, and some others are also discussed.