Advances in Food Oral Processing: Mechanisms of Bolus Formation, Multidimensional Evaluation, and Applications Across Food Categories

Oral processing plays a central role in food texture perception, bolus formation, and swallowing safety, thereby influencing consumer acceptance and nutritional outcomes. This review summarizes recent advances in food oral processing, focusing on the mechanisms of bolus formation, multidimensional evaluation approaches, and applications across diverse food categories. The mechanisms underlying bolus formation are discussed with emphasis on the interactions among food composition, structure, masticatory dynamics, and saliva. Major evaluation methods, including sensory evaluation, physicochemical characterization, and dynamic biomimetic simulation, are systematically reviewed. These approaches enable the analysis of temporal sensory perception, structural transformation, flavor release, and rheological and tribological properties during mastication. Their integration provides complementary insights into the dynamic evolution of food in the oral phase. The applicability of these methods across different food matrices is further examined. Distinct oral processing behaviors are identified in fibrous and tough systems, porous and brittle structures, and gel-like or viscoplastic materials, reflecting matrix-specific breakdown mechanisms and saliva interactions. Considerations for specific populations, such as infants, older adults, and individuals with dysphagia, are also highlighted to support tailored food design. Future research directions are discussed with an emphasis on predictive and personalized frameworks, including the emerging role of digital twin technology in simulating oral processing and supporting precision food engineering.