Work

Coffee Bean Characterization Using Terahertz Sensing

Year: 2025

Type: article

Abstract: Coffee bean sorting is currently based primarily on visual appearance and near-infrared techniques that probe the bean's skin. However, sorting based on compositional differences has significant potential to optimize the roasting process. We present a novel coffee bean sorting method using terahertz (THz) spectroscopy, which effectively penetrates both green and roasted beans. Our findings show that the optical properties of coffee beans at THz frequencies are primarily governed by internal moisture levels. To demonstrate industrial feasibility, we implement a robot-guided THz sensing system capable of scanning beds of beans for automated sorting. More broadly, our results confirm the potential of THz technology for moisture content analysis across various applications.

Source: Sensors

DOI: 10.3390/s25072096

Authors: Dook van Mechelen, Daan Meulendijks, Milan Koumans

Institution: Eindhoven University of Technology

Language: English

Topic: Terahertz technology and applications

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $3,137