Spatial flavor metabolomics: probing food flavor distribution with MALDI-MSI technology

Flavor formation and expression exhibit significant spatial heterogeneity. However, traditional homogenization-based methods obscure tissue structure, limiting mechanistic insights. This review defines Food Spatial Flavor Metabolomics (FSFM) as an operational framework centered on spatial variables. Within FSFM, imaging technologies like matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) provide indispensable evidence for elucidating precursor localization, migration gradients, and co-localization modules. Synthesizing data across food systems, we identify shared spatial patterns: interfacial enrichment, gradient migration, functional co-localization, and processing-induced remodeling. Despite these advances, volatile loss, matrix effects, and quantitative reproducibility remain critical bottlenecks. Consequently, we outline methodological decision rules, clarifying when to prioritize spatial imaging versus coupling it with conventional analyses. By aligning technical capabilities with application scenarios, this review provides a structured roadmap for FSFM to transition from a conceptual initiative to a standardized research paradigm.