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Related Experiment Video

Updated: May 14, 2025

Terahertz Imaging and Characterization Protocol for Freshly Excised Breast Cancer Tumors

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Coffee Bean Characterization Using Terahertz Sensing.

Dook van Mechelen¹, Daan Meulendijks¹, Milan Koumans¹

¹Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.

Sensors (Basel, Switzerland)

|April 12, 2025

Summary

This summary is machine-generated.

This study introduces terahertz (THz) spectroscopy for sorting coffee beans by internal moisture. This novel method offers a more accurate approach than visual inspection for optimizing the roasting process.

Keywords:

THz spectroscopy coffee bean sorting moisture level of coffee beans optical properties of coffee beans

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Area of Science:

Agricultural Science
Spectroscopy
Food Science

Background:

Current coffee bean sorting relies on visual inspection and near-infrared (NIR) spectroscopy, which primarily analyze the bean's surface.
Sorting based on internal composition, such as moisture content, holds significant potential for optimizing coffee roasting.
Existing methods lack the ability to effectively probe the internal properties of coffee beans non-destructively.

Purpose of the Study:

To develop and demonstrate a novel coffee bean sorting method utilizing terahertz (THz) spectroscopy.
To investigate the correlation between THz optical properties and internal moisture levels in coffee beans.
To assess the industrial feasibility of THz spectroscopy for automated coffee bean sorting.

Main Methods:

Terahertz (THz) spectroscopy was employed to analyze both green and roasted coffee beans.
A robot-guided THz sensing system was developed for automated scanning of bean beds.
The relationship between THz optical properties and internal moisture content was investigated.

Main Results:

Terahertz (THz) spectroscopy effectively penetrates coffee beans, providing insights into internal properties.
The optical properties of coffee beans at THz frequencies are strongly correlated with internal moisture levels.
The implemented robot-guided THz system demonstrated industrial feasibility for automated sorting.

Conclusions:

Terahertz (THz) spectroscopy offers a novel and effective method for sorting coffee beans based on internal moisture content.
This technology has the potential to significantly optimize the coffee roasting process by enabling composition-based sorting.
The findings confirm the broader applicability of THz technology for non-destructive moisture content analysis in various materials.