Multiscale time-domain NMR for structural, water, and texture characterization of meat and plant-based food matrices: a mini review

Time-domain nuclear magnetic resonance (TD-NMR) is a powerful, non-destructive method for probing water mobility, molecular dynamics, and hierarchical structure in complex food matrices. Over the past several decades, numerous studies have demonstrated that relaxation, diffusion, and relaxometry-derived parameters are closely linked to microstructural constraints, water distribution, texture, and water-holding capacity (WHC) in both muscle and plant-based systems. This mini review synthesizes foundational and recent advances into a unified multiscale TD-NMR framework spanning molecular (μs-ms), mesoscopic (μm), and macroscopic (mm-cm) levels. We show how T₁/T₂ relaxation, diffusion coefficients, and multidimensional correlation methods can be mapped onto structural and functional properties of native meat and engineered plant-based matrices. Integrating these TD-NMR modalities with microstructural imaging and texture profiling provides a quantitative approach for mechanistic understanding and product optimization. Future opportunities include machine-learning tools for multidimensional datasets, physics-guided inversion algorithms, and the development of industrial, inline TD-NMR sensing platforms.