Microencapsulation of Lactobacillus rhamnosus HN001 by spray drying and its evaluation under gastrointestinal and storage conditions

The consumption of Lactobacillus rhamnosus HN001 enhances human gastrointestinal health. However. L. rhamnosus viability decreases during food processing, storage, and gastric conditions. In this study, L. rhamnosus cells were encapsulated by spray drying using gum arabic blended with agave fructans, malto-dextrin, inulin, or trehalose as wall materials. Probiotic microcapsules were characterized by encapsulation efficiency and scanning electron microscopy, as well as the viability of L. rhamnosus in vitro simulated gastrointestinal tract and storage conditions (4 and 20 degrees C), and physicochemical characteristics such as water activity, moisture content, hygroscopicity, and solubility. Microcapsules showed high encapsulation efficiency (84%-93%). The morphology did not show ruptures or cracks on the surface of microcapsules. Gum arabic/ trehalose blend preserved probiotic viability with less than 1 log CFU g(-1) of loss after eight weeks at 4 degrees C and less than 3 logs CFU g(-1) of loss after eight weeks in aw<0.33 at 20 degrees C. The powders produced with gum arabic/ trehalose showed the highest viability under simulated gastrointestinal conditions. The physicochemical characteristics of the powders were suitable to protect the viability of probiotics during production and under gastrointestinal conditions, prolonging their shelf life without compromised the beneficial health effects.

Automated summary

The study successfully encapsulated Lactobacillus rhamnosus cells using gum arabic blended with various materials, protecting their viability. The selection of materials and encapsulation method significantly impacted the performance of microcapsules.