Effect of chitosan-alginate encapsulation with inulin on survival of Lactobacillus rhamnosus GG during apple juice storage and under simulated gastrointestinal conditions

• Probiotic encapsulation improved bacterial survival during apple juice storage.
• Encapsulation improved probiotic survival during gastrointestinal transition.
• Probiotic encapsulation had no adverse organoleptic effect on apple juice.
• Inulin addition increased survival of encapsulated bacteria in gastrointestinal conditions during the storage period.

In the present study the effects of encapsulation with alginate and chitosan, with or without inulin, on viability of probiotic Lactobacillus rhamnosus GG in apple juice during 90 days storage at 4 and 25 °C were evaluated. Moreover, the probiotic survival under simulated gastrointestinal conditions and sensory attributes during apple juice storage were investigated. The survival rate of free bacteria decreased to 13.6% through the storage. The encapsulated L. rhamnosus experienced greater survival rate which was 4.5 times higher than that of free bacteria at day 90. Encapsulation of L. rhamnosus improved bacterial viability since 27.7% of bacterial population survived gastrointestinal transition model. Furthermore, inulin addition had a significant positive effect (p < 0.05) on survival of encapsulated bacteria. The sensory scores showed that the probiotic encapsulation brought an improvement in all characteristics. The results of this research suggested the encapsulation of probiotic bacteria as an effective method to improve bacterial survival both during apple juice storage and in gastrointestinal condition without any adverse organoleptic effect.