Spray freeze drying method for microencapsulation of Lactobacillus plantarum

Microcapsules containing Lactobacillus plantarum (MTCC 5422) was produced by SFD technique with wall material formulations namely (i) whey protein isolate (WPI) with sodium alginate (SA), (ii) WPI with fructooligosaccharide (FOS), (iii) denatured-WPI (DWPI) with SA, and (iv) DWPI with FOS. The effect wall materials on physical properties of microcapsules, encapsulation efficiency and cell viability during storage were evaluated. Freeze drying (FD) has been used as a control method to evaluate the efficacy of SFD. The findings revealed that SFD microcapsules were spherical in shape and exhibited, 'good' flowability, and lower hygroscopicity. Microencapsulation by SFD method did not affect the cell viability as indicated by good encapsulation efficiency (87.92-94.86%). Among the SFD microcapsules, DWPI + FOS had higher encapsulation efficiency and better stability during storage. SFD technique overcomes long drying time and lack of control on the microcapsules size and shape. Hence, the SFD can be a suitable technique for microencapsulation of probiotics.