Application and research progress of dietary fiber-based fat substitutes in food systems

The rising global burden of diet-related noncommunicable diseases has accelerated the development of low-fat foods that retain desirable sensory and functional properties. Dietary fibers, leveraging their unique water-holding capacity, gelling behavior, and tunable rheology, have emerged as versatile fat replacers across diverse food matrices. This review synthesizes recent advances in the design and application of dietary-fiber-based fat substitutes, categorizing them into two primary classes: Abbas et al. (2024) (1) fat-free mimetics (hydrogels and particulate systems) and (Akal, 2023 (2)) fat-based substitutes (fiber-stabilized emulsions, emulsion gels, and oleogels). Key strategies to enhance fiber functionality, including chemical, enzymatic, and physical modifications for hydrophobicity enhancement, and synergistic composites with proteins or lipids, are critically evaluated. Representative applications in meat products, dairy systems, baked goods, and spreads are analyzed, emphasizing improvements in texture, water/fat retention, oxidative stability, and nutritional profiles. Persistent challenges include replicating the crispness and melt behavior of full-fat analogs, ensuring the safety of modified fibers, balancing essential fatty acids and fat-soluble vitamins, and optimizing gastrointestinal tolerance. Future directions encompass multi-component mimetics (e.g., protein-fiber complexes and polysaccharide-lipid hybrids), sustainable modification technologies (enzymatic/physical treatments), and precision replacement strategies guided by nutritional genomics and microbiome science. Interdisciplinary collaboration and supportive policy frameworks will be pivotal in advancing dietary-fiber-based fat substitutes toward a new paradigm of 'healthy, palatable, and safe' low-fat foods.