Abstract Probiotics incorporated into edible film coatings (EFC) represent an innovative technology to enhance probiotic delivery and stability in functional foods. The present study aims to develop and evaluate the effectiveness of an EFC in protecting the viability of three probiotic lactic acid bacteria (LAB) strains in acidic conditions, in food matrices, and during storage. EFC consisted of hydrocolloidal biomolecule whey protein concentrate, sodium alginate, and glycerol (2: 0.5: 0. 5% w/v). Three well-characterized probiotic LAB strains, Lacticaseibacillus paracasei K-04, Lactiplantibacillus plantarum M-02, and Lacticaseibacillus rhamnosus SM, were isolated from Egyptian fermented foods and encapsulated using standardized EFC protocol. The biscuits and dry dates were fortified with a multistrain probiotic mixture encapsulated in EFC probiotic LABs. The morphology of the probiotics LAB strains was characterized by scanning electron microscopy (SEM). The safety assessment of the three LAB strains was conducted based on their antibiotic susceptibility and hemolytic activity. Survival was assessed under acidic pH and simulated gastric digestion (SGD). Antibacterial activity against pathogenic bacteria, antioxidant capacity, and probiotic viability during storage of functional probiotic biscuits (FPB) were also evaluated. None of the studied LAB strains exhibited hemolytic activity, indicating an absence of virulence-associated traits. Furthermore, all strains demonstrated susceptibility to most of the tested antibiotics, with resistance limited to a few agents. The total viable LAB count averaged 5.39 x 107 CFU/g in biscuit and 1.60 x 107 CFU/g in dry dates. The EFC LAB strains exhibited significantly higher survival rates (P 0.05) than the respective free cells. The same trend was obtained with simulated gastric digestion (SGD). Interestingly, EFC forms showed enhanced antibacterial activity compared to the respective free against all tested pathogenic bacteria (P 0.05). Similarly, the antioxidant activity of EFC was significantly higher (P 0.05) compared to the respective free forms. The FPB and FPD had no adverse effect on the sensory characteristics. After 4 weeks of storage at 4 °C, FPB maintained viable LAB counts above 1.08 x 106 CFU/g of biscuit, exceeding the minimum recommended threshold. The ingredients used for the development of the functional biscuits and dates are locally sourced, tasteless, cost-effective, and environmentally sustainable. The introduction of these probiotic-enriched products into the Egyptian food systems offers, as they align with traditional dietary habits and require no significant changes in consumer behaviour. This approach represents an accessible and practical strategy to promote public health and contribute to disease prevention at the population level.
Gad et al. (2025) studied this question.