Portable Agtron Number Analysis Device and Agtron Number Analysis Method

Portable Roasting Degree Determination Device Based on Coffee Bean Image Red Value Learning

This technology is an analysis method and portable device that determines the Agtron number, an indicator of roasting degree, using only camera images without grinding the coffee beans. It creates training data for R (Red) values by class from images of coffee beans with known Agtron numbers to establish threshold values, then compares the R value of the measured coffee beans against these thresholds.

Roasting is affected by daily humidity and temperature, making it essential to verify the roasting degree. However, the traditional method of expert estimation using Agtron tiles is inaccurate and labor-intensive. Commercially available Agtron analyzers cost thousands to tens of thousands of dollars, making them inaccessible to small roasteries and home baristas.

This technology calculates the Agtron number through simple comparison by using the intersection points of Gaussian distribution graphs of R-value frequencies for each class as threshold values. A light source and a detachable black funnel create a darkroom environment to maintain consistent shooting conditions. It can be applied to quality control in coffee roasteries and home coffee equipment, allowing for professional-level roast degree determination without expensive colorimeters.

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Key Features:

• Capturing multiple images of coffee beans with known Agtron numbers and acquiring training data for R values by class
• Creating Gaussian distribution graphs of R values and frequencies by class using the training data and determining the intersection points of neighboring graphs as class threshold values
• Capturing an image of the target coffee beans with a camera to obtain the R value and determining the Agtron number by comparing it with the class threshold values
• A portable analysis device equipped with memory storing class threshold values, a camera, a control unit for determination, an output unit, and a detachable black funnel that forms a darkroom around the light source

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