Milk Based Extrusion Method For Microencapsulation of Probiotics

Abstract

Probiotics are the live microorganism which when administered in adequate amount imparts health and nutritional benefits to the host. When they are ingested orally they have to go through low gastric pH and bile salts that decrease their survival to reach to the colon. Also when free probiotics are incorporated into product then they have to go through different physiological and chemical conditions during food processing and storage as a result of which their viability count decreases. Therefore, to improve the viability count of probiotics they are microencapsulated which provide them a suitable microenvironment helping them to maintain their viability count. In the present study microencapsulation using extrusion with sodium alginate and skimmed milk (coating material) in the 1:1 ratio was conducted for already reported proboitic Lactobacillus gastricus BTM7. Calcium Chloride was used as a hardening solution. Free and microencapsulated bacteria were evaluated for their viability count in gastrointestinal condition and during storage. The encapsulation increased the survival of probiotics under simulated gastric and pancreatic conditions as compared to free cells. During the storage in skimmed milk based media, a higher survival of 96.1% was obtained for microencapsulated probiotics as compared to 84.1% survival of free cells. Therefore, these results indicate that microencapsulation provides protection to probiotics against gastrointestinal conditions and during storage of the probiotic food products.