Spectroscopic Study of Volatile Organic Compounds for the Assessment of Coffee Authenticity
Arianna Elefante1,2, Marilena Giglio2, Lavinia Mongelli2
1Consiglio Nazionale delle Ricerche (CNR), Istituto di Fotonica e Nanotecnologie, 70126 Bari, Italy.
Molecules (Basel, Switzerland)
|September 13, 2025
Summary
This study defines infrared spectral signatures of volatile organic compounds (VOCs) for coffee authentication. These unique VOC fingerprints can help differentiate coffee origins, improving quality control.
Area of Science:
- Analytical Chemistry
- Food Science
- Spectroscopy
Background:
- Volatile organic compounds (VOCs) play a crucial role in coffee aroma and quality.
- Accurate authentication and quality control of coffee beans are essential for the food industry.
- Existing methods for coffee analysis may not fully capture the nuances of origin-specific chemical profiles.
Purpose of the Study:
- To establish distinct infrared spectral signatures for key volatile organic compounds (VOCs) found in coffee.
- To explore the potential of Fourier Transform Infrared Spectroscopy (FTIR) for coffee bean authentication.
- To develop a method for discriminating coffee origin based on VOC spectral data.
Main Methods:
- Fourier Transform Infrared Spectroscopy (FTIR) was used to obtain high-resolution mid-infrared absorption spectra (0.1 cm-1).
- Analysis focused on representative coffee VOCs: Pyridine, 2-Methylpyrazine, 2,5-Dimethylpyrazine, Furfural, 5-Methylfurfural, and Furfuryl Alcohol.
- Multilinear regression was applied to analyze mixtures of these VOCs, simulating their concentrations in coffee.
Main Results:
- Distinct infrared spectral signatures were identified for the analyzed coffee-related VOCs.
- The study demonstrated that VOC signatures within absorption spectra can be used for coffee fingerprinting.
- Successful discrimination of coffee origin was shown to be feasible using this spectroscopic approach.
Conclusions:
- Infrared spectroscopy provides valuable spectral signatures for key coffee VOCs.
- VOC spectral fingerprinting using FTIR is a promising technique for coffee authentication.
- This method offers a potential pathway for reliable discrimination of coffee bean origin and quality assessment.
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