Routine Analysis of Fortified Foods using Single Quadrupole ICP-MS

Significance of the Topic

Fortified food products are widely consumed and regulated for essential nutrient levels and toxic metal contaminants. Analytical methods with high sensitivity and broad dynamic range are required to ensure consumer safety and meet regulatory standards.

Objectives and Study Overview

This work demonstrates a routine multi element screening method using a single quadrupole ICP-MS to quantify 28 major and trace elements in fortified foods. The study aims to validate method accuracy, precision, and robustness through analysis of reference materials and commercial samples.

Methodology and Instrumentation

For sample preparation, approximately 0.2 g of sample was microwave digested in nitric acid then diluted to 50 mL. Instrumentation comprised an Agilent 7800 ICP-MS with a helium collision cell (ORS4) in kinetic energy discrimination mode, a standard sample introduction system, and an SPS 4 autosampler. Collision gas flows were 5 mL/min for most elements and 10 mL/min for selenium. Calibration used multi element standards in 5 per cent nitric acid. Dynamic range spanned 10 orders of magnitude, and high matrix introduction handled up to 3 per cent total dissolved solids.

Main Results and Discussion

Analytical detection limits and method limits of quantitation were all below regulatory levels. Calibration curves were linear across the mass range and matrix tolerance was demonstrated by internal standard recovery within ±20 per cent over 140 analyses spanning six hours. Spike recovery tests for seven regulated elements yielded 95 to 109 per cent. Analysis of NIST 1849a reference material gave recoveries within 10 per cent of certified values for 13 nutrient elements. Commercial samples from the USA and China showed essential elements within guideline ranges and toxic metals well below maximum levels.

Benefits and Practical Applications

The described method enables simultaneous quantitation of high concentration minerals and trace contaminants in a single run. Its high throughput and robustness suit food quality control laboratories for compliance verification, nutritional labeling, and contamination screening.

Future Trends and Applications

Further developments may include enhanced interference removal technologies, automated sample digestion workflows, and integration with high resolution mass spectrometry for speciation studies. Expansion to other complex matrices such as beverages and dietary supplements is anticipated.

Conclusion

A single quadrupole ICP-MS workflow provides a fast, accurate, and robust solution for multi element analysis of fortified foods. Validation using SRM, spike tests, and commercial samples confirms its suitability for routine food testing in regulatory and industrial settings.

References

• GB 10765-2010 National Food Safety Standard Infant Formula, Ministry of Health of China
• 21 CFR 107 Infant Formula, US Food and Drug Administration
• Commission Delegated Regulation (EU) 2016/127, Official Journal of the European Union
• GB 5009.268-2016 Determination of minerals in foods for infants and young children, Chinese national standard
• ISO 20649:2015 Infant Formula and Adult Nutritionals ICP-MS method
• ISO 21424:2018 Milk, milk products, and nutritionals ICP-MS method for minerals and trace elements
• CODEX Standard 193-1995 General Standard for Contaminants and Toxins in Food and Feed