Analysis of 3-MCPD Fatty Acid Esters and Glycidol Fatty Acid Esters in Palm Oil Using GC-MS/MS in Accordance with AOCS Method Cd 29c-13

Analysis of 3-MCPD Fatty Acid Esters and Glycidol in Palm Oil Using GC-MS/MS (AOCS Method Cd 29c-13)

Significance of the topic

3-MCPD fatty acid esters and glycidol esters form during high-temperature refining of edible oils and pose potential carcinogenic risks. Regulatory bodies such as the European Commission set strict limits on their levels in oils and fats for consumer safety. Sensitive and reliable analysis in matrices like palm oil is essential to ensure compliance and protect public health.

Objectives and Study Overview

This work demonstrates the development and validation of a multiple reaction monitoring GC-MS/MS method using the Shimadzu GCMS-TQ8050 NX with backflush for quantifying 3-MCPD and glycidol in palm oil. The study follows AOCS Method Cd 29c-13, aiming for low detection limits, high reproducibility, and compliance with EU regulations.

Methodology and Instrumentation

Sample preparation employs two assays: Assay A (cleavage in the presence of chloride ion) converting glycidol to 3-MCPD and Assay B (absence of chloride) to quantify native 3-MCPD and glycidol separately. Both assays include ester cleavage, liquid–liquid extraction, and derivatization with phenylboronic acid. Calibration uses a 5-point matrix-matched curve for 3-MCPD and 3-level glycidol spiking to determine the glycidol-to-3-MCPD transformation factor.

• Instrument: Shimadzu GCMS-TQ8050 NX triple quadrupole GC-MS/MS with Shimadzu Backflush System
• Column: SH-I-17Sil MS (30 m × 0.25 mm ID × 0.25 µm df)
• Carrier gas: Helium, splitless injection at 250 °C
• Oven program: 85 °C to 150 °C at 6 °C/min, then to 210 °C at 12 °C/min, finally to 280 °C at 30 °C/min
• MRM transitions optimized for target analytes and internal standard (3-MCPD-d5)

Main Results and Discussion

The 3-MCPD calibration curve showed excellent linearity (R² = 0.9997). The glycidol-to-3-MCPD transformation factor was determined as t = 0.83. Analytical performance achieved a LOQ of 0.02 µg/g and a calculated LOD of 0.006 µg/g for 3-MCPD. Recoveries ranged from 94 % to 118 % for both analytes at the LOQ level. Inter-day repeatability (n=7 over four days) yielded RSDs below 5 %.

Benefits and Practical Applications

• High sensitivity allows detection well below regulatory maximum limits
• Optimized sample preparation reduces analysis time compared to earlier AOCS methods
• Backflush system prevents column contamination, extending column life
• Applicable for routine QA/QC in edible oil refining and food safety laboratories

Future Trends and Applications

The approach can be extended to other edible oils and fats, and adapted for high-throughput screening of multiple processing contaminants. Coupling with automated sample preparation and expanding the method to include additional analytes will enhance monitoring capabilities in food safety and regulatory compliance sectors.

Conclusion

The described GC-MS/MS method on the Shimadzu GCMS-TQ8050 NX with backflush meets the requirements of AOCS Method Cd 29c-13, delivering robust quantitation of 3-MCPD and glycidol in palm oil with excellent sensitivity, accuracy, and precision. It supports regulatory compliance and routine quality control in edible oil processing.

Reference

1. EFSA Panel on Contaminants in the Food Chain (CONTAM). Process contaminants in vegetable oils and foods. EFSA Journal, 2016.
2. Commission Regulation (EU) 2020/1322 of 23 September 2020 amending Regulation (EC) No 1881/2006 on maximum levels of 3-MCPD, 3-MCPD esters, and glycidyl esters in certain foods. Official Journal of the European Union, 2020.