Multiscale Coupling From Mastication to Retronasal Aroma Perception: The PG-DTCFN Model and Multiphysics Simulation

Retronasal olfaction is central to food flavor perception, yet its multiscale mechanisms from the oral processing to the central nervous system lack systematic elucidation. This study employs grilled lamb skewers as a model, integrating multi-dimensional data and simulations to construct a research paradigm tracing the pathway from bolus release to central perception. Results reveal that extended grilling time increases bolus hardness and chewing force, with the 12 min sample exhibiting a collision intensity of 1.128, establishing a dual-kinetic profile for aroma release. Efficiently transported aroma molecules target the olfactory cleft region, with characteristic volatile compounds substantially enriched at 30 s of chewing. Electroencephalogram (EEG) analysis distinguishes basic neural encoding of isolated aroma from multisensory cross-modal integration during eating, with enhanced coupling between prefrontal alpha asymmetry and midline theta power (r = 0.36), delineating an inferred three-stage framework from peripheral input to reward-associated cortical responses. This framework is proposed based on EEG spatiotemporal patterns and source localization results, providing a testable model for future mechanistic studies. A physics-guided dual-timescale cross-field interaction network achieves high-accuracy, interpretable prediction of retronasal aroma intensity, while a complementary multiphysics simulation reproduces the complete physical process from chewing to nasal transport. This study pioneers a unified framework integrating macro-scale processing, meso-scale bolus evolution, micro-scale molecular transport, and neural responses, providing a transferable methodological paradigm for flavor science.