Authenticating Coffee Origins With Vibrational Spectroscopy – CoffeeTalk

A study published in Food Innovation and Advances introduces new methods for authenticating coffee origins, supporting the industry’s commitment to quality and traceability. Vibrational spectroscopy, traditionally used in pharmaceutical and forensic science, is now being used in agriculture for quality control and origin verification of biological products. Techniques such as near-infrared (NIR), mid-infrared (FTIR), Raman, and hyperspectral imaging (HSI) spectroscopy offer rapid, non-destructive analysis of food items. However, variations in sample properties can introduce noise into spectral data, affecting accuracy. To mitigate these issues, preprocessing spectral data is essential to remove physical artifacts and improve model reliability.

The study compared four vibrational spectroscopy techniques—dispersive near-infrared (DG-NIR), near-infrared hyperspectral imaging (HSI-NIR), attenuated total reflectance Fourier transform infrared (ATR-FTIR), and Raman spectroscopy—by applying various preprocessing methods to classify coffee samples from Indonesia, Ethiopia, Brazil, and Rwanda. The primary challenges involved three specific spectral data issues: offsets, slopes, and curvature, each impacting signal accuracy.

To tackle these challenges, the spectra were mean-centered before further analysis, and no outliers were detected in any of the datasets. Preprocessing techniques, including normalization, scatter correction, and spectral derivations, are crucial for removing physical artifacts. Matthew’s Correlation Coefficient (MCC) was applied as a primary decision metric to handle data imbalances. This approach enabled the identification of optimal preprocessing treatments for each instrument, enhancing the accuracy of coffee origin classification across various countries.

Read More @ Azo Optics