Improvement of the viability of encapsulated probiotics using whey proteins

The viability of Lactobacillus acidophilus encapsulated in calcium alginate particles coated with up to three levels of multilayer was analysed. Probiotic survival under simulated gastrointestinal conditions, thermal treatment and storage conditions were also investigated, as well as the morphology and mean particle size. The encapsulation efficiency obtained was higher than 80% in all multilayer treatments, while the diameter ranged from 107 μm to 222 μm among the different numbers of particle layers. Microencapsulated L. acidophilus presented viability during the simulated gastrointestinal conditions, and the treatment with a layer of whey protein (A1) provided greater protection for the probiotics in all the stages of the analysis, with final count of 9.19 CFU g−1. In the thermal resistance tests, the multilayer particles promoted greater protection for probiotic cultures in relation to the free cells that did not resist the tested conditions. The storage for up to 120 days at refrigeration and freezing temperatures were more efficient for all types of multilayer microparticles when compared to free cells. The results suggest that multilayer microparticles present an effective method to improve the probiotic viability during storage, thermal treatments and gastrointestinal conditions.