Differential Analysis of Olive Oils with Pegasus GC-HRT and ChromaTOF-HRT ® ® Reference Feature

Importance of the Topic

Characterizing volatile compounds in olive oils is critical for quality control, brand protection and detection of adulteration. High resolution accurate mass spectrometry coupled with gas chromatography provides the sensitivity and confidence needed to distinguish complex aroma and flavor profiles in food matrices.

Objectives and Study Overview

This study aimed to perform a non-targeted volatile analysis of extra-virgin and light olive oils from the same producer, using high resolution GC-TOFMS and automated data processing to identify sample-specific markers and evaluate the potential for fraud detection.

Methodology and Instrumentation

The experimental workflow combined headspace solid-phase microextraction with high resolution GC-TOFMS and advanced software analysis:

• Sample preparation: 2 g oil in a 10 mL SPME vial, incubated at 40°C for 5 min and extracted for 25 min
• SPME fiber: 50/30 μm DVB/CAR/PDMS
• GC conditions: Rxi-5ms column (30 m × 0.25 mm × 0.25 μm), helium at 1.5 mL/min, temperature program from 40°C to 250°C
• MS conditions: Pegasus GC-HRT in high resolution mode (25 000 FWHM), mass range 33–400 m/z, 6 spectra/s, source at 250°C
• Data analysis: LECO ChromaTOF-HRT software with the Reference feature for automated peak finding, classification and comparison of analytes against a reference sample

Main Results and Discussion

Chromatographic overlays revealed numerous differences between extra-virgin and light olive oils. Automated classification assigned each analyte to categories based on its presence or relative concentration compared to the reference:

• Not Found: present only in the reference sample
• Unknown: present only in the sample
• Match: present at similar levels in both
• Out of Tolerance: present in both but with significant concentration differences

Key distinguishing compounds included:

• α-Cubebene (sesquiterpene): detected exclusively in extra-virgin oil
• Phenylethyl alcohol: lower concentration in light oil, indicative of extra-virgin quality
• Heptane: elevated levels in light oil, characteristic of refined oil

Accurate mass measurements below 1 ppm reinforced library matches and ensured confident identifications across multiple fragment ions.

Benefits and Practical Applications

This differential analysis approach offers rapid feature selection and robust authentication, enabling:

• Efficient screening for adulteration and labeling fraud in olive oils
• Quality control monitoring of aroma and flavor profiles
• Development of targeted markers for routine analysis

Future Trends and Opportunities

Advancements may include integration of machine learning for automated pattern recognition, expansion of high resolution databases for broader compound coverage and real-time monitoring capabilities for on-line quality assurance. Further applications can extend to other edible oils and complex food matrices.

Conclusion

The combination of Pegasus GC-HRT and ChromaTOF-HRT software enables high resolution, accurate mass profiling and automated comparative analysis of olive oils. This approach delivers clear differentiation between product grades and supports reliable detection of food fraud through sample-specific volatile markers.

Used Instrumentation

• SPME fiber: 50/30 μm DVB/CAR/PDMS
• GC-TOFMS: Pegasus GC-HRT with Rxi-5ms column
• Software: LECO ChromaTOF-HRT with Reference feature