Automated LC-GC system for MOSH and MOAH analysis in food, according to EN 16995:2017

Significance of MOSH and MOAH Analysis in Food Safety

MOSH (mineral oil saturated hydrocarbons) and MOAH (mineral oil aromatic hydrocarbons) are food contaminants originating from packaging materials, lubricants or environmental sources. Even at trace levels, they may pose health risks, so monitoring their presence in edible oils, fats and other food matrices is essential to meet stringent EU (EFSA) and US (FDA) regulatory limits and to protect consumers.

Objectives and Study Overview

This work presents an automated LC-GC/FID system designed to streamline the analysis of MOSH and MOAH in food according to EN 16995:2017. The goals were to automate sample preparation (including saponification and epoxidation), enable on-line injection into a hyphenated LC-GC system, improve data accuracy and precision, and increase sample throughput for routine QA/QC laboratories.

Methodology and Instrumentation

A modular analyzer integrates:

• TriPlus RSH SMART autosampler equipped with heater/agitator, centrifuge, vortex, fast wash and automatic tool change for automated saponification (KOH) and epoxidation (mCPBA) steps
• Vanquish HPLC normal-phase system with silica-gel column for fractionation of MOSH and MOAH
• TRACE 1600 auxiliary oven hosting injection, transfer and backflush valves to maintain heated sample paths
• TRACE 1610 GC-FID dual-channel system configured for large-volume transfers into separate MOSH and MOAH capillary columns
• Chromeleon CDS software controlling all modules, managing e-Workflows for sequence setup, data acquisition, processing and automated reporting

Main Results and Discussion

System qualification with retention time markers and internal standards demonstrated recoveries within 90–110% and chromatographic resolution >2 for critical peaks. Repeatability tests on mineral oil standards yielded RSDs below 1% for both MOSH and MOAH fractions. Automated sample preparation delivered consistent epoxidation, as verified by the absence of squalene interference in MOAH chromatograms and RSDs below 5% for spiked olive oil samples. Optional modules, such as aluminum-oxide cleanup, further improved MOSH quantitation by removing natural n-alkanes. Chromeleon e-Workflows reduced sequence-setup time to three clicks, minimizing human error.

Benefits and Practical Applications

The fully automated LC-GC/MS system offers:

• High throughput and reproducible analysis of MOSH and MOAH in diverse food matrices
• Reduced manual handling and risk of contamination
• Improved data integrity through integrated software control and automated QC checks
• Flexible configuration to accommodate cleanup modules or fraction collection for off-line GC or GC-MS profiling
• Customizable reporting templates compatible with LIMS

Future Trends and Possibilities

Emerging directions include coupling LC-GC to GC×GC-MS for detailed hydrocarbon fingerprinting, integrating additional automated preparative steps (e.g., solid-phase extraction), leveraging AI-driven data evaluation for anomaly detection, and deploying cloud-based data management to facilitate collaborative QA/QC workflows. Continued regulatory refinement may drive lower detection limits and more stringent cleanup requirements.

Conclusion

This automated LC-GC/FID solution, complemented by robotic sample preparation and advanced software control, delivers robust, high-throughput analysis of MOSH and MOAH in food. Its modular design and e-Workflow capabilities enable laboratories to meet evolving regulatory demands while ensuring data quality and operational efficiency.

References

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