Coffee Color Measurement

Coffee, one of the most widely consumed beverages in the world, offers a rich variety of flavors and aromas. For coffee producers and roasters, maintaining consistent quality is essential. One crucial factor in achieving this consistency is the color of the coffee, which indicates the bean’s origin, roasting process, and flavor profile. Different roast levels produce different coffee tastes and acidity. For instance, Light roasts are known for their fruity, floral notes and higher acidity. Medium roasts offer a balanced combination of flavor and acidity, showcasing more complex flavors. In contrast, dark roasts emphasize bitterness and smoky flavors. Accurate color measurement is vital in ensuring that coffee beans are roasted to the desired level, directly influencing the flavor, aroma, and overall consumer experience.

Methods of Coffee Color Measurement

Coffee color measurement can performed after the roasting process. Traditionally, coffee producers and roasters relied on visual assessments to determine roast level. However, this method can be subjective and prone to human error, as different individuals may perceive colors differently depending on lighting conditions, experience, etc. To overcome this subjectivity, instrumental color measurement techniques have emerged as the industry standard in the coffee industry, providing objective and repeatable evaluations.

Instrumental color measurement techniques utilizing spectrophotometers or colorimeters operate by illuminating coffee beans and measuring the amount of light reflected. These instruments then process the data and convert it into specific color information. Additionally, color measurements can be performed on ground coffee, which offers a more uniform surface for analysis. This approach enhances accuracy and consistency, as variations in particle size can influence light reflection and, consequently, color measurement.

When it comes to measuring the color of coffee, two of the most widely used color spaces are CIE L*a*b* and CIE L*C*h. The CIE L*a*b* is a sophisticated 3-dimensional model that comprises three key components: L* (lightness), which ranges from 0 (representing black) to 100 (indicating white), a* (the red-green axis), and b* (the yellow-blue axis) On the other hand, the CIE L*C*h color space describes color differently by utilizing cylindrical coordinates. It incorporates L* for lightness, C* for chroma that reflects the intensity or saturation of the color, and h* for hue, which indicates the specific type of color.

Alternatively, there are also specialized indices designed for coffee color measurement. One notable example is the Specialty Coffee Association of America (SCAA) coffee index, which assigns numerical values to the color of coffee beans, corresponding to different roast levels such as light, medium, medium-dark, and dark. This allows coffee producers and roasters to measure the color of ground or whole-bean coffee and compare it to the industry benchmark.

Konica Minolta Sensing Color Measurement Solutions for the Coffee Industry

Konica Minolta Sensing, a leader in color management solutions, provides a comprehensive range of spectrophotometers and colorimeters that are widely utilized in the food industry. Notably, the Chroma Meter CR-410C Coffee Meter and the Spectrophotometer CM-5 are invaluable tools for evaluating and managing color throughout various stages of coffee production, including sorting, roasting, and grading.

The Konica Minolta CR-410C Coffee Meter is a handheld color measurement instrument that can help coffee producers and roasters measure and grade the color of ground or whole-bean coffee quickly and precisely. Besides the CIE L*a*b* and CIE L*C*h color spaces, the CR-410C Coffee Meter also comes equipped with the SCAA Speciality coffee index, which includes classifications for roast levels (light, medium, medium dark, dark) and pass/fail tolerances.

The Konica Minolta Spectrophotometer CM-5 is a highly versatile color measurement instrument capable of both reflectance and transmittance color measurements. With a comprehensive range of accessories, the CM-5 can handle various coffee samples, including beans, powders, or liquids. When paired with the color data software SpectraMagic NX2, the CM-5 enables the creation of customized color evaluation formulas tailored to specific applications. Check out the CM-5 video to explore its features and capabilities further.