Evaluation of viability of bacteria using in vitro gastro intestinal model and formulation of functional food with synbiotic microcapsules

Abstract

Probiotic microbes are proved to offer beneficial effects to human health by several researchers all over the world. Microbes are required to have some essential characters in order to be utilized as probiotics. One of the important characters is to resist the stress conditions of stomach (pH 2.0 and digestive enzyme pepsin) and small intestine (bile and pancreatic enzymes). To check the efficiency of microbial isolates for ability to transit stomach and small intestine in a viable state, in vitro gastro intestinal model is used. In vitro gastro intestinal model assembled in Department of Fermentation and Biosynthesis, Faculty of Food Science and Nutrition, Poznan University of Life sciences, Poznan consists of three compartments namely (i) automatic pH controller, (ii) acid and alkali dispenser, and (iii) water bath with magnetic stirrer. Eleven bacterial isolates were checked in free and encapsulated form and five of them were found to be tolerating the stress conditions of stomach and small intestine. It was also found that encapsulation protects the bacteria from stress conditions and enhances their survival. Synbiotic microcapsules were prepared using mushroom extract as prebiotic sources. Synbiotic microcapsules were incorporated with health mix to form dry functional food. Survivability of bacteria in dry functional food was checked at pre-determined time intervals and the results revealed that bacteria retained viability in dry food during storage period.