HIGH THROUGHPUT ANALYSIS OF MOSH AND MOAH IN FOOD AND PACKAGING

Importance of the Topic

The monitoring of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) in food and packaging is vital for public health and regulatory compliance. MOSH and MOAH may migrate into food from recycled cardboard and processing equipment. MOAH, in particular, is suspected of containing carcinogenic compounds, prompting the need for sensitive, reliable analytical methods.

Objectives and Study Overview

This work describes a high-throughput, fully automated online LC-GC method that integrates normal-phase liquid chromatography with gas chromatography to separate and quantify MOSH and MOAH in a single 30-minute run. The system employs the CHRONECT® LC-GC interface and dual-FID detection to minimize solvent use and double sample throughput.

Methodology and Instrumentation

Sample preparation follows standard hexane extraction, with modifications such as activated alumina clean-up or epoxidation to remove biogenic hydrocarbons and olefins in complex matrices. The LC step fractionates MOSH and MOAH while excluding lipids and matrix interferences. An intelligent valve setup transfers 450 µL of each fraction via a retention gap and solvent vapor exit to the GC.

Instrumentation Used

• Agilent 1260 Infinity LC with binary pump, UV detector and degasser
• CTC PAL autosampler
• CHRONECT® LC-GC interface for fraction transfer
• Agilent 7890B GC equipped with two FID channels operating in parallel
• OpenLAB CDS ChemStation and Chronos software for instrument control and data analysis

Key Results and Discussion

The combined LC-GC method achieves limits of quantitation of 0.5 mg/kg for both MOSH and MOAH in rice and noodles. Parallel FID detection reduces analysis cost and solvent consumption by 50%. The system delivers excellent reproducibility, high sensitivity and supports continuous 24/7 operation. Chromatograms demonstrate clear separation of MOSH (green trace) and MOAH (black trace) from complex food matrices, eliminating the need for two separate GC runs.

Benefits and Practical Applications

• High sample throughput with 30 min per analysis
• Fully automated workflow reducing contamination risk
• Improved sensitivity and reproducibility
• Cost savings through reduced solvent use and dual-channel detection
• Scalability to additional analytes such as sterols and PAHs

Future Trends and Potential Applications

Emerging developments may include further miniaturization, integration with mass spectrometry for enhanced selectivity, and software-driven data interpretation using AI. Expanded applications could target a broader range of food contaminants and packaging migrants.

Conclusion

The fully automated Agilent LC-GC solution with CHRONECT® coupling offers a robust, high-throughput approach for simultaneous MOSH and MOAH determination. With low LOQs, reduced costs and reliable performance, the method supports routine quality control and regulatory compliance in food analysis.

References

1. Biedermann M, Fiselier K, Grob K. Journal of Agricultural and Food Chemistry. 2009;57(18):8711-8721.