Non-Intentionally Added Substances in Food and Food Contact Material – Determination of Mineral Oil Hydrocarbons with LC-GC Online Technique

Importance of the Topic

Mineral oil hydrocarbons (MOH) are non-intentionally added substances in food and food contact materials that can pose potential health risks. Accurate and sensitive detection of saturated (MOSH) and aromatic (MOAH) fractions is crucial for consumer safety and regulatory compliance.

Objectives and Study Overview

This study presents an online HPLC-GC-FID technique for routine determination of MOSH and MOAH in various food matrices and contact materials. It aims to enhance reproducibility, minimize manual sample preparation, and increase analytical throughput.

Methodology and Instrumentation Used

Samples (1–10 g) are homogenized, spiked with internal standards, and extracted with hexane/ethanol (1:1). After liquid–liquid washing, drying over sodium sulfate, and automated concentration to 1 mL, aliquots are injected into the LC-GC system.

Instrumentation comprises a Shimadzu Nexera platform with dual LC-20ADXR pumps, CBM-20A LITE controller, SPD-20A UFLC UV detector, GC-2010 Plus FID detectors, PAL autosampler, and CHRONOS/LabSolutions software. Advanced features include fract & collect fractionation for detailed MOH analysis and online epoxidation to remove natural interferences.

Main Results and Discussion

The method achieves clear separation and quantification of MOSH and MOAH, with high sensitivity and reproducibility. In a recycled paper grade sample, MOSH C16–C35 was measured at 787 ± 99 mg/kg and MOAH C16–C35 at 110 ± 12 mg/kg. Direct LC-GC coupling eliminated manual SPE steps and improved system stability.

Benefits and Practical Applications

• High reproducibility and accuracy comparable to split/splitless injection
• Reduced solvent consumption and GC contamination via direct LC–GC interface
• Automated workflow supports high sample throughput for QA/QC and regulatory monitoring

Future Trends and Potential Applications

• Integration with GC–MS, GC×GC–MS or GC–TQMS for detailed hydrocarbon profiling
• Use of fract & collect for enhanced MOAH sensitivity
• Extension to broader NIAS screening in food contact materials and recycled substrates

Conclusion

The online HPLC-GC-FID approach offers a robust, automated solution for MOSH/MOAH determination in food and contact materials, ensuring reliable results, regulatory compliance, and high laboratory throughput.

Reference

1. EFSA Journal 2012;10(6):2704
2. Commission Recommendation (EU) 2017/84 of 16 January 2017
3. EN 16995:2017 Foodstuffs – Vegetable oils and foodstuff on basis of vegetable oils – Determination of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) with on-line HPLC-GC-FID analysis
4. Nestola M., Schmidt T.C. J. Chromatogr. A 1505 (2017) 69–76