Maillard conjugates produced from proteins and prebiotic dietary fibers: Technological properties, health benefits and challenges

Modifying proteins through the Maillard reaction has garnered significant attention from researchers. The amino group of a protein and the carbonyl group of a carbohydrate covalently interact, forming conjugates. The production of conjugates is compelling due to the improvement of protein properties, such as emulsification, solubilization, foam formation ability, antioxidant capacity, kinetic stability, and even reduction of allergenicity. Producing conjugates via the Maillard reaction is a strategy that can enhance the utilization of proteins with limited technological properties. Furthermore, the use of prebiotic fibers as a source of carbonyl for covalent bonds with proteins allows for the creation of a new functional ingredient. This new ingredient can be used for targeted and selective delivery of proteins to intestinal probiotics. The conjugates are characterized by their resistance to gastrointestinal digestion, ensuring that a portion of the protein reaches the colon. The prebiotic fraction of the conjugate imparts selectivity for the growth and proliferation of probiotics. This review provides an overview of the main concepts of the Maillard reaction and the factors that influence the reaction rate. We highlighted the use of prebiotic dietary fibers to enhance the technological and functional properties of the proteins. Additionally, we emphasized the production of a functional ingredient targeted towards colonic probiotics because of the covalent bonding between prebiotic dietary fibers and proteins. The protein-carbohydrate conjugation via the Maillard reaction can be a promising strategy for enhancing proteins' technological and functional properties. These conjugates should be produced under controlled conditions of temperature, time, type, and size of the carbohydrate, protein-carbohydrate ratio, and pH, aiming to limit the reaction to the initial stage. Thus, there is a significant challenge in finding and controlling the optimal process conditions that ensure the improvement of the techno-functional properties of proteins. Additionally, protein/carbohydrate conjugates may possess immunomodulatory and anti-inflammatory capabilities, making them suitable for targeted delivery to the intestinal microbiota. This turns them into promising ingredients for both the food and pharmaceutical industries.