A sustainable analytical approach for detecting extra virgin olive oil adulteration using Nexera™ UC

Significance of the Topic

Extra virgin olive oil (EVOO) is widely valued for its nutritional quality and commands a premium price, making it a frequent target for economic adulteration. Reliable detection of inferior seed oils in EVOO is vital for consumer protection, regulatory compliance, and maintaining industry standards. Adopting green analytical practices further supports environmental goals by reducing solvent use and waste.

Goals and Study Overview

The study aimed to establish a fast, simple, and ecofriendly subcritical fluid chromatography with UV detection method to quantify triacylglycerol profiles in EVOO adulterated with soybean, corn, and peanut oils at levels from 5 to 50% (v/v). Statistical tools were applied to differentiate pure and adulterated samples.

Methodology and Instrumentation

Samples were prepared by blending EVOO with seed oils at defined ratios and vortexing for homogeneity without additional pretreatment. Analyses were conducted on a Nexera UC SFC-PDA system equipped with four Ascentis Express C18 columns in series, a CO2 pump, ethanol modifier pump, column oven, PDA detector, and backpressure regulator. The mobile phase comprised CO2 with 5% ethanol in isocratic mode at 2.0 mL/min, 25°C, 200 bar, with UV detection at 205 nm.

Main Results and Discussion

The four-column arrangement achieved baseline separation of TAGs within 30 minutes. Elution order correlated with partition number and unsaturation degree, reflecting hydrophobicity differences. One-way ANOVA identified several TAG markers (e.g., LLL) that significantly varied with adulterant level. Principal component analysis clearly separated pure EVOO from samples containing more than 5% seed oil. The AGREE greenness assessment scored the SFC-PDA method at 0.83 versus 0.48 for conventional nonaqueous reversed-phase HPLC, demonstrating superior sustainability.

Benefits and Practical Applications

• Minimal organic modifier consumption (5%)
• Rapid analysis time (30 minutes)
• No sample pretreatment required
• Reduced solvent use and waste compared to HPLC
• Suitable for routine quality control and authenticity testing

Future Trends and Opportunities

Further enhancements may include coupling with mass spectrometry for increased sensitivity, extending the approach to other food matrices, developing inline chemometric tools for real-time decision making, lowering modifier requirements, and exploring portable SFC platforms for field analyses.

Conclusion

The developed green SFC-PDA method on a Nexera UC system delivers efficient, sustainable triacylglycerol profiling in EVOO and robustly detects common seed oil adulterants, making it a promising tool for routine authenticity and quality assessments.

Reference

• Lesellier E, Latos A, Lopes de Oliveira A. Ultra high efficiency/low pressure supercritical fluid chromatography with superficially porous particles for triglyceride separation. Journal of Chromatography A. 2014.
• Torres-Cobos B, Quintanilla-Casas B, Vicario G, Guardiola F, Tres A, Vichi S. Revealing adulterated olive oils by triacylglycerol screening methods: Beyond the official method. Food Chemistry. 2023.
• Lesellier E, Latos A, West C. Ultra high efficiency/low pressure supercritical fluid chromatography (UHE/LP-SFC) for triglyceride analysis: Identification, quantification, and classification of vegetable oils. Analytical Science Advances. 2020.