In-house validation of accelerated solvent extraction-gas chromatography-mass spectrometry for the determination of bound 3- and 2-monochloropropanediols (MCPD) and glycidol in food products

ABSTRACT

The study aimed to establish the detection method for bound 3-, 2-MCPD, and glycidol using accelerated solvent extraction (ASE) and gas chromatography mass spectrometry (GC-MS). The ASE was modified for reduced solvent volume and process time to extract lipid from the chocolate spread, infant formula, potato chips, and sweetened creamer. The solvent selected for ASE was a mixture of iso-hexane and acetone at 100°C with the lipid and analyte recovery ranging from 96.9% to 98.6% and 84.1% to 107.5%, respectively. The derivatisation of analytes was adopted from the AOCS method Cd29a-13 for GC-MS analysis. The results showed that the coefficient of determination (R²) of all analytes was >0.99. The limit of detection (LOD) was 0.1 mg kg⁻¹ expressed in lipid basis for both bound 3- and 2-MCPD and 0.2 mg kg⁻¹ expressed in lipid basis for bound glycidol. The limit of quantitation (LOQ) was 0.3 mg kg⁻¹ expressed in lipid basis for both bound 3- and 2-MCPD and 0.6 mg kg⁻¹ expressed in lipid basis for bound glycidol. A blank spiked with 3-monochloropropanediols fatty acid esters (MCPDE) and 2-MCPDE (0.3, 2.1, and 7.2 mg kg⁻¹) and glycidol esters (0.6, 4.7, and 16.6 mg kg⁻¹) were chosen for accuracy and precision tests. The recoveries were 91.7% to 105.9%. Both repeatability and within-laboratory reproducibility of the analysis were within the acceptable level of precision ranging from 1.7% to 16%. This is the first time that a full validation procedure extending to both accuracy and precision tests has been carried out for sweetened creamer and chocolate spread. Overall, the combined protocol of ASE and AOCS Cd29a-13 was successfully validated for both solid and liquid food samples with lipid content from 10% to 30%.

KEYWORDS:

• GC-MS
• ASE
• Bound 3-MCPD
• Bound 2-MCPD
• bound glycidol

Acknowledgments

The authors would like to thank the Director General of Health Malaysia for the permission to publish this paper. Special gratitude is also dedicated to the Food Safety and Quality Division, Ministry of Health Malaysia for funding this research work and Food Safety and the Quality Laboratory State of Selangor, Ministry of Health Malaysia for laboratory facility and technical support.

Disclosure statement

The authors have declared no conflict interest.

Additional information

Funding

This work was supported by the Food Safety And Quality Division, Ministry of Health, Malaysia.