# Preparation and Characterization of Multilayered Microcapsules of Lacticaseibacillus rhamnosus Encapsulated With Sodium Alginate, Jujube Mucilage, and Whey Protein Isolate in Goat Milk Dessert

## TL;DR

A dual-layer microencapsulation system protects probiotic bacteria in goat milk desserts, improving survival and texture.

## Contribution

A novel dual-layer encapsulation system using jujube mucilage and whey protein isolate was developed to enhance probiotic stability in dairy products.

## Key findings

- The optimized formulation (6:4 jujube mucilage to whey protein isolate) achieved 94.16% encapsulation efficiency.
- Microencapsulated probiotics showed 75.48% survival during storage and 70.98% under simulated gastrointestinal conditions.
- Incorporation into goat milk desserts improved acidity, hardness, and texture without affecting adhesiveness or springiness.

## Abstract

This research aimed to investigate the ability of a two‐layer extrusion encapsulation technique to protect Lacticaseibacillus rhamnosus (LR) during simulated gastrointestinal conditions (SGC) and heat stress. The microcapsules were made with alginate as the first layer, whereas the second layer consisted of jujube mucilage and whey protein isolate (WPI). The encapsulation efficiency (EE%), microstructure, and survival rate (SR%) under heat stress were assessed to determine the best formulation for addition to a goat milk dessert (GMD). The number of LRs during storage, microstructure, acidity, and texture were evaluated during storage. The microencapsulated LR (MLR) received the highest EE% rating. It contained JM and WPI at a ratio of 6:4 (94.16%) (JW3). JW3 had the best SR (69.14%) after 15 min of heat stress. The GMD containing MLR‐JW3 (GMD‐MLR‐JW3) demonstrated a superior SR in terms of storage (75.48%) and SGC (70.98%) than did the GMD containing free LR (GMD‐FLR). The incorporation of MLR‐JW3 led to increases in acidity (20.98°D), hardness (47.25 ± 1.25 g), cohesiveness (0.51 ± 0.02), gumminess (24.15 ± 0.35 g), and chewiness (1.4 ± 0.04 mJ), but adhesiveness and springiness were nearly constant among the GMD samples. Scanning electron microscopy demonstrated that the addition of beads led to a decrease in the quantity of pores and casein aggregates, culminating in a denser microstructure within the GMD‐MLR. This research highlights the effective implementation of a dual‐layer microencapsulation system aimed at improving LR survival and functionality in GMDs, thereby providing enhanced probiotic stability and texture for the advancement of functional food development.

A dual‐layer microencapsulation system composed of alginate, jujube mucilage, and whey protein isolate effectively protected Lacticaseibacillus rhamnosus under heat and simulated gastrointestinal conditions. The optimized formulation (JM:WPI, 6:4) achieved the highest encapsulation efficiency (94.16%). Incorporation into goat milk dessert improved probiotic stability, acidity, hardness, and overall texture, highlighting its potential for functional dairy product enhancement.