Food chemical metrology: a critical review of measurement uncertainty, metrological traceability, and analytical applications

Food metrology is essential to ensure the reliability, comparability, and regulatory compliance of analytical results in food systems. This review addresses the principles of measurement uncertainty and metrological traceability, based on key frameworks such as the ISO Guide to the Expression of Uncertainty in Measurement (GUM), EURACHEM guidelines, and recommendations from INMETRO. Measurement uncertainty, defined as a parameter associated with the dispersion of values attributed to a measurand, is critical for the interpretation of analytical data and decision-making in food quality, safety, and authenticity. The ISO-GUM provides a structured approach for identifying and combining uncertainty sources, while EURACHEM offers practical strategies tailored to chemical and food analysis. These approaches are particularly important for complex food matrices, where sampling, matrix effects, and instrumental variability significantly influence results. Metrological traceability ensures that measurements are linked to recognized reference standards through an unbroken calibration chain, supporting data comparability across laboratories. Analytical platforms such as HPLC, LC-MS/MS, ICP-MS, NMR, and vibrational spectroscopy (FTIR and NIR) are discussed as representative examples of how measurement uncertainty and metrological traceability are implemented in food chemical analysis. In food analysis, the integration of uncertainty estimation and metrological traceability underpins compliance with regulatory limits, risk assessment, labeling accuracy, and fraud detection. Emerging trends combining metrology with advanced analytical techniques and chemometrics further strengthen data reliability and transparency in the global food chain.