Simple Method for Screening Analysis of Vegetable Oils Using a Single Quadrupole Mass Spectrometer

Importance of the Topic

Composition of vegetable oils influences nutritional value, oxidative stability and quality control. Rapid screening of fatty acids supports health trend demands and ensures product authenticity and refinement status in food industry.

Objectives and Study Overview

The study introduces a streamlined screening method for fatty acids and related components in eight commercial vegetable oils using a single quadrupole LC-MS with flow injection, targeting high throughput and reliable fatty acid profiling.

Methodology and Instrumentation

• Sample preparation: Eight vegetable oils (soybean, rapeseed, sunflower, olive, grapeseed, coconut, linseed, perilla) diluted 100× in 2-propanol with 10 ppm DHA as internal standard.
• Instrumentation: Shimadzu Nexera XR system coupled to LCMS-2050 (single quadrupole). Flow injection using methanol mobile phase (flow ramp from 0.1 to 1 mL/min over 1 min).
• MS conditions: ESI/APCI DUIS in positive/negative scan mode (m/z 50–2000), interface voltage ±3.0 kV, gas flows (nebulizing 2 L/min, drying 5 L/min, heating 7 L/min), desolvation 500 °C, DL 250 °C.
• Data analysis: Spectra exported to JCAMP format via LabSolutions, followed by multivariate analysis (PCA) using eMSTAT Solution.

Main Results and Discussion

Negative-mode screening detected 118 peaks. PCA clustered oils into four groups corresponding to predominant fatty acid types: omega-3 (α-linolenic), omega-6 (linoleic), omega-9 (oleic), and medium-chain (e.g., lauric). Relative intensities normalized to DHA yielded fatty acid compositions matching reference values within acceptable ranges, demonstrating accuracy of the approach.

Benefits and Practical Applications

This flow-injection LC-MS method enables one-minute per sample analysis with minimal maintenance, suitable for high-throughput quality control, authenticity testing, and monitoring of oil refinement and oxidation.

Future Trends and Applications

Integration with automated data pipelines and machine learning algorithms may enhance pattern recognition. Expansion to additional lipid classes and real-time process monitoring in production lines can further improve food quality and traceability.

Conclusion

The presented single quadrupole LC-MS screening method offers rapid, robust and accurate fatty acid profiling of vegetable oils, supporting routine quality control and research in food science.

References

• Kaneda Co., Ltd. List of Vegetable Oils and Fats, accessed November 14 2023.