Advances in food-grade hydrogel encapsulation of probiotics with next-generation prebiotics for targeted synbiotic delivery

Background. Hydrogel-based encapsulation represents a successful method for preserving probiotics and their functionality during processing, storage, and gastrointestinal transit. Although conventional systems offer protection, advances in next-generation prebiotics such as polyphenols and non-digestible carbohydrates have shifted the focus toward multifunctional synbiotic delivery systems. These materials provide sustainable, food-grade design and improve both structural integrity and bioactivity. Additionally, fabrication and crosslinking methods such as ionic interactions, Maillard conjugation, and enzymatic or pH-responsive techniques facilitate precise hydrogel customization for targeted probiotic release. Scope and approach. This review discusses recent progress in natural and composite hydrogels for probiotic encapsulation, with particular attention to the influence of next generation prebiotics on hydrogel functionality. A decision-oriented design framework is presented, aligning target sites and release triggers with materials and crosslinking strategies, exemplified with quantitative results. This framework offers a systematic approach for selecting food-grade matrices and encapsulation methods. Key findings and conclusions. Natural and composite hydrogels provide effective protection against oxygen, heat, acidity, bile salts, and digestive enzymes, maintaining a hydrated and biocompatible microenvironment. Protein–polysaccharide combinations increase mechanical and rheological stability, while next-generation prebiotics further reinforce structural integrity and bioactivity. Encapsulation efficiencies above 90 percent and enhanced cell viability in simulated digestion demonstrate promising performance of these systems. The integration of quantitative mapping and design principles establishes a practical framework for developing scalable, food-grade, multifunctional synbiotic hydrogels, supporting advancements in probiotic delivery technology. Adopting standardized digestion models and prioritizing in vivo validation will aid the development of synbiotic hydrogels acceptable in real food systems.