Electrospraying microencapsulation of Lactobacillus plantarum enhances cell viability under refrigeration storage and simulated gastric and intestinal fluids

• Lactobacillus plantarum was effectively microencapsulated using the electrospraying technique.
• The survival of microencapsulated cell was high in simulated gastric and intestinal juices.
• Microencapsulated cell survival under long periods of storage was high.
• Results show very high survival rates compared to previous immobilization systems.

Electrospraying was used to microencapsulate Lactobacillus plantarum in sodium alginate or in sodium alginate-citric pectin matrixes. Immobilized cells and control (free cells) were tested for survival when exposed to simulated gastric acid and intestinal juices (SGJ and SIJ). Results showed control viability losses of 6 and 4.2 log CFU mL−1 when exposed for 120 min to SGJ and SIJ, whereas microencapsulated cells decreased by 2.9 CFU mL−1 in SGJ, and 2.7 CFU mL−1 in SIJ. Refrigeration storage for 21 days showed cell survivals around 9 log CFU mL−1 for immobilized cells, whereas for the control the survival, it was around 1 log CFU mL−1. Microcapsules presented a particle size distribution in the interval of 7 to 2000 µm. FTIR spectra confirmed Ca2+ complexation of alginate and pectin structures obtained by electrospraying. Results demonstrate the efficiency of this technique to increase the survival of L. plantarum in the digestive system of hosts.