Prebiotics in the microencapsulating matrix enhance the viability of probiotic Lactobacillus acidophilus LA1

The viability of microencapsulated Lactobacillus acidophilus LA1 beads containing different levels of fructo-oligo-saccharides (FOS - 1.5%, 2.5% and 3%) and partially hydrolysed guar gum (PHGG - 3% and 5%) were studied under different conditions of pH (1.0, 2.0), bile salt concentrations (1%, 1.5% and 2%) and high temperature exposure (75° and 85° C). The microcapsules had 8–9 log of viable cells of L. acidophilus LA1. Cells entrapped in alginate beads with no prebiotic (CAB) and containing prebiotic (PAB) were incubated at 37°C under the test conditions of pH, bile and temperature for different lengths of time. Survival rates decreased with increasing incubation periods at the experimental levels of pH, bile concentrations and severity of heat. PAB survived significantly better than CAB at higher levels of the prebiotic concentrations. The matrix with 3% PHGG, 3% alginate, and 2% starch performed well at all test conditions.