Effect of Three Polysaccharides (Inulin, and Mucilage from Chia and Flax Seeds) on the Survival of Probiotic Bacteria Encapsulated by Spray Drying

Chia seed mucilage (CM), flaxseed mucilage (FM), and inulin (INL) were used as encapsulating agents to evaluate the possibility of increasing the survival of Lactobacillus casei var. rhamnosus, renamed recently to Lacticaseibacillus rhamnosus, after spray drying. Moreover, the viability of encapsulated L. rhamnosus was determined during the 250 day storage period at 4 °C. In a second stage, the conditions that maximized the survival of L. rhamnosus were evaluated on other probiotic bacteria (Lactiplantibacillus plantarum, Bifidobacterium infantis, and Bifidobacterium longum). Additionally, the viability of encapsulated probiotics during the 60 day storage period at 4 and 25 °C was evaluated. The conditions that maximize the survival of L. rhamnosus (90%) predicted by a face-centered central composite design were 14.4% w/v of maltodextrin, 0.6% w/v of CM, and 90 °C of inlet air temperature. Additionally, under these encapsulating conditions, the survival of L. plantarum, B. infantis, and B. longum was 95%, 97%, and 96%, respectively. The probiotic viability improved during storage at 4 °C but decreased at 25 °C. The highest viability values obtained for probiotics during spray drying and during storage suggest a thermoprotector effect of CM, which would ensure an optimal probiotic efficacy in the product, thus promoting its utilization in the food industry.