In this study, a novel combination of biopolymers, that is, sodium alginate (Na-Alg), whey protein isolates (WPI) combined with prebiotic fructo-oligosaccharide (FOS) were used to encapsulate Lactobacillus rhamnosus GG via extrusion method. The obtained synbiotic microbeads were characterized for diameter and encapsulating efficiency. Morphological and molecular characterizations was done using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), x-ray diffraction, and thermal stability by Thermogravimetric analysis. In addition, viability of encapsulated probiotic under in vitro simulated gastrointestinal conditions were evaluated. The results indicated that the prepared beads had a diameter of 1.13 mm on average and encapsulation efficiency of 93%. According to SEM micrographs, probiotics were successfully loaded in the microbeads. The FTIR spectra revealed strong bonding between the encapsulating materials indicating stable matrix formulation. Viability under simulated gastrointestinal conditions was significantly enhanced. Na-Alg, WPI, and FOS composite microbeads have the potential to enhance stability as well as viability of Lactobacillus rhamnosus GG. The results indicate that this novel synbiotic encapsulation can be useful for the application of probiotics in food products and food systems. Enhanced viability under simulated gastrointestinal conditions shows that this encapsulating matrix can be used for better probiotic delivery. The Na-Alg/WPI/FOS matrix significantly enhanced probiotic survival, indicating its potential for improved probiotic delivery via food systems.
Keywords: Lactobacillus rhamnosus GG; fructo‐oligosaccharide; microencapsulation; prebiotic; probiotic; sodium alginate; synbiotic; whey protein isolate.
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