Fast Analysis of Fatty Acids in Brans by GC/MS

Importance of the Topic

Rapid and reliable measurement of fatty acids in food matrices such as brans is critical for nutritional profiling, quality control, and research into functional ingredients. Traditional gas chromatography methods can be time-consuming and may yield ambiguous peak identification, which can delay decision making in both research and industrial settings.

Objectives and Study Overview

This study aimed to develop a high-throughput GC-MS method for the quantitation of 37 fatty acid methyl esters (FAMEs) in bran samples. As part of a collaboration between Shimadzu Corporation and the National Agriculture and Food Research Organization (NARO), researchers sought to reduce analysis time while maintaining confidence in peak identity and quantitation.

Methodology

Sample preparation involved direct methylation of fatty acids using a commercial Fatty Acid Methylation Kit. A sample mass of approximately 0.1 g was converted to FAMEs in a single-step reaction.

Použitá instrumentace

• Gas chromatograph–mass spectrometer: GCMS-QP™2020 NX
• Auto injector: AOC™-20i Plus
• Auto sampler: AOC-20s Plus
• Analytical column: DB-FastFAME (20 m × 0.18 mm I.D., 0.20 µm film)
• Injection liner: Split liner with wool

Analytical Conditions

Carrier gas was helium under constant linear velocity control (53.4 cm/s). The column oven program started at 60 °C, ramped at 40 °C/min to 200 °C, then 25 °C/min to 250 °C, for a total run time of 10.5 minutes. Injection was performed in split mode (10:1) at 250 °C. The mass spectrometer operated with a Smart EI/CI ion source at 230 °C (ion source) and 250 °C (interface). Simultaneous Scan/SIM acquisition covered m/z 35–600 at 20,000 µ/s, with isobutane as the CI reagent gas.

Main Results and Discussion

The optimized method achieved full separation and accurate quantitation of 37 FAMEs in a 10-minute run. Calibration curves for representative compounds (C4:0 to C20:4) showed correlation coefficients (R2) greater than 0.99 across relevant concentration ranges. The Smart EI/CI ion source enabled seamless switching between electron impact and chemical ionization modes in the same batch, allowing confirmation of peak identities without manual source changes.

Benefits and Practical Applications

• Increased productivity by reducing run time to 10 minutes for FAME 37 analyses.
• Improved confidence in compound identification through simultaneous EI/CI data acquisition.
• Straightforward method transfer to GC-FID owing to constant linear velocity control.

Future Trends and Opportunities

Ongoing developments may include further acceleration of fatty acid profiling workflows, integration with automated sample preparation systems, and application to a broader range of food and environmental matrices. Enhanced data processing algorithms and hybrid ionization sources could extend the method to trace-level analyses and complex lipid classes.

Conclusion

The fast GC-MS method using a Smart EI/CI ion source provides a robust, high-throughput approach for fatty acid analysis in brans. It combines rapid separation, reliable identification, and excellent quantitation performance, meeting the needs of both research and quality-control laboratories.

Reference

No external literature references were provided in the source document.