Microencapsulation of Lactobacillus plantarum (MTCC 5422) with fructooligosaccharide as wall material by spray drying.

Microencapsulation is a promising technique for delivery of live microbial supplements through foods.
Prebiotics like ‘fructooligosaccharide (FOS)’ can be used as a wall material to produce synbiotics. However,
the low glass transition temperature (Tg) of FOS causes stickiness when used as wall material during
spray drying. This problem was alleviated by FOS in combination with whey protein isolate (WPI) or
denatured whey protein isolate (DWPI) for encapsulating the probiotic bacteria Lactobacillus plantarum
(MTCC 5422). Microencapsulation was performed with wall materials FOS, FOS þ WPI, FOS þ DWPI at
two different core-to-wall ratios of 1:1 and 1:1.5. FOS þ WPI and FOS þ DWPI microcapsules of 1:1 coreto-
wall ratio exhibited higher encapsulation efficiency, lower residual moisture content and narrow
range of particle size distribution than 1:1.5. However, microcapsules of 1:1.5 core-to-wall ratios
enhanced the storage stability and tolerance of probiotic cells in the simulated gastric and intestinal
conditions. FTIR analysis confirmed the presence of whey proteins and FOS in the microcapsules after
spray drying. On overall comparison, FOS þ DWPI microcapsules of 1:1 core-to-wall ratio had higher
encapsulation efficiency (98.63%) but 1:1.5 ratio exhibited better storage stability and protection in
simulated gastric, as well as intestinal condition than the other encapsulates.