MOSH&MOAH in food ingredients and additives and the advantages of using LC/GC×GC(-FID/TOFMS) for their analysis

Importance of the Topic

Mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) are widespread petroleum-derived contaminants in food matrices.
They can enter the food chain via packaging, processing equipment or storage and pose health risks due to tissue accumulation and genotoxicity.
EFSA has underlined a lack of comprehensive data on these impurities in oil-derived food additives.

Objectives and Overview

• Gather quantitative and qualitative data on MOSH/MOAH levels in food additives in response to EFSA recommendations.
• Compare conventional HPLC-GC-FID with advanced HPLC/GC×GC-FID/TOFMS workflows.

Methodology and Instrumentation

Sample Preparation:
- Solid or liquid food samples undergo solvent extraction to isolate hydrocarbon fractions.
- HPLC-based purification separates MOSH and MOAH fractions and enables further MOAH sub-fractionation by aromatic ring count.

Instrumental Setup:

• HPLC: Normal-phase chromatographic separation of hydrocarbon classes.
• GC×GC: Comprehensive two-dimensional gas chromatography with cryogenic modulator for enhanced resolution.
• Detectors: Flame ionization (FID) for total hydrocarbon quantitation; time-of-flight mass spectrometry (TOFMS) for selective PAH detection and structural insights.

Main Results and Discussion

• GC×GC chromatograms exhibit structured patterns that facilitate identification of linear, branched and aromatic hydrocarbon classes and remove co-eluting interferences.
• HPLC fractionation successfully isolates MOAH sub-fractions (1-2 rings versus ≥3 rings), meeting EFSA’s recommendation for detailed characterization.
• Mass spectrometric markers such as 2,6-diisopropylnaphthalene (DIPN) pinpoint contamination sources (e.g., recycled paperboard packaging).
• Combined analysis demonstrates simultaneous quantitation of MOAH humps by FID and trace-level PAHs by TOFMS without additional cleanup.
• LC purification approach yields superior PAH recoveries (90–110%) compared to traditional epoxidation protocols.

Benefits and Practical Applications

• Improved analytical selectivity and sensitivity addresses regulatory LOQs for MOSH (0.5–1 mg/kg) and PAHs (0.9 µg/kg).
• Enhanced structural resolution aids risk assessment and compliance reporting.
• Marker-based source tracking supports contamination prevention strategies.
• Streamlined workflow reduces analysis time and resource consumption.

Future Trends and Applications

Advances in chromatography, automation and data processing will further increase throughput and robustness.
Integration with high-resolution MS and multidimensional separations could broaden applications to other hydrocarbon contaminants.
Developing standardized protocols will facilitate regulatory adoption and inter-lab comparability.

Conclusion

The HPLC/GC×GC-FID/TOFMS approach, though more complex than routine methods, offers substantial gains in resolution, selectivity and comprehensive analysis of MOSH, MOAH and PAHs in food additives.
These capabilities align with EFSA recommendations and support more reliable contaminant monitoring.

References

• Biedermann M., Grob K. J. Chromatogr. A 1375 (2015) 146–153.
• Gorska A., Bellinghieri C., Albendea P., Purcaro G. Analytical Chemistry – Gembloux Agro-Bio Tech, 2025.