Viability assessment of microencapsulated probiotics in carbonated soft drinks during storage and simulated gastrointestinal conditions

In recent years, the addition of probiotics into non-dairy beverages has gained popularity. Probiotics offer a wider range of options for individuals who are sensitive to dairy products. Incorporating probiotics into widely consumed beverages like carbonated soft drinks poses a notable challenge due to the detrimental impact of acidic pH. Herein, results demonstrate that chitosan-coated alginate/gellan gum microcapsules can enhance the viability of probiotics within carbonated soft drinks. The probiotics, Lactobacillus casei, are encapsulated in microcapsules and exposed to Pepsi, Fanta Strawberry, Sprite, and A&W Root Beer under 4 and 25°C for 60 days and simulated gastrointestinal tract. Microcapsules greatly improve the viability of adding probiotics in different beverages under simulated gastrointestinal tract. The probiotics had a gradual release from microcapsules, reaching maximum release within initial 2 h of simulated intestinal phase. During 4°C storage compared to storage at 25°C, it was found that the number of surviving cells is more than the recommended minimum (10⁶ CFU/g) at the end of the storage. The pH and soluble solids content of beverages containing microcapsules also signify little change. This work shows that the chitosan-coated alginate/gellan microcapsules have the potential to be used as protective microcapsules for probiotics in carbonated soft drinks.