Assuring food safety and traceability of polished rice from different production regions in China and Southeast Asia using chemometric models

摘要

A novel strategy combining elemental analysis-isotopic ratio mass spectrometry (EA-IRMS) and inductively plasma coupled mass spectrometry (ICP-MS) analysis with chemometric data-processing was applied to differentiate polished rice from different growing regions in China with rice imported from Southeast Asia (Thailand and Malaysia). Seven stable isotope ratios (i.e. delta C-13, delta N-15, delta H-2, delta O-18, (87/86)sr, (207/206)pb and Pb-208/207) and 25 multielemental concentrations (Na, Ca, Fe, Zn, Rb, Ag, and Cd, etc.) were assayed and used to establish principal component analysis (PCA) and step-wise linear discriminant analysis (LDA) modeling to determine the rice's geographical origin. The prediction accuracies were cross-validated, and "blind sample" tests were all higher than 90.0% for rice samples from different production areas in China and 85.0% for rice imported from Southeast Asia, respectively. The high level of geographical traceability when combining stable isotope and multielement fingerprints with chemometric data-processing provides a promising tool to assure the origin of Chinese polished rice. This authentication method protects premium rice brands, combats commercial fraud, and quickly locates the origin of contaminated Cd rice to add verifiable food safety measures for consumers.