Viability of Lactobacillus plantarum NCIMB 8826 immobilized in a cereal-legume complementary food “weanimix” with simulated gastrointestinal conditions

Abstract

Three cereal-legume complementary foods (weanimix) were formulated and evaluated for their ability to enhance the survival of probiotic bacteria Lactobacillus plantarum NCIMB 8826 in simulated gastrointestinal tract conditions. The three different blends of weanimix: MCPPM (maize:cowpea:peanut:powdered milk), MCP (maize:cowpea:peanut) and MC (maize:cowpea) were used. L. plantarum was inoculated and cultured in the weanimix slurry media to immobilize the cells. L. plantarum free cells in MRS broth were used as a control. Simulated gastric fluid (SGF) of pH 2.5, 3.0 and 3.5, and bile salt (0.3 and 1 g/100 ml of ox gall) were used to simulate the gastrointestinal conditions. The three complementary blends offered a protective shield, which improved cell viability in SGF at all pH levels. L. plantarum survived well in MCPPM, MCP and MC with <2 log cell reduction compared with the free cells reduction of ~5 log after 180 min of incubation for each pH. For bile tolerance, viable cell counts in the weanimix were higher than the free cells after 24 h suspension. The results of the study showed that weanimix improved the survival and viability of L. plantarum.