Impact of Correlated Color Temperature on Red Meat Color Assessment via Image Processing Systems

Abstract

The color of red meat significantly influences consumer perception and purchasing decisions, making accurate color evaluation crucial for the meat industry. This study examines how the correlated color temperature (CCT) of the light source affects various color parameters (L, a*, b*, C*, hue angle, and redness index) of red meat samples analyzed using an image processing system (IPS). Meat samples were photographed under adjustable LED lighting with CCT ranging from 2900 to 7800 K, while controlling for illumination intensity and ensuring a color rendering index (CRI) above 95. The results showed that while the lightness (L*) values remained statistically unchanged (p > 0.05), the redness (a*) and yellowness (b*) values were significantly affected by CCT (p < 0.05). Specifically, the a* value peaked at 5100 K, and the b* values increased sharply at CCTs above 6900 K. The hue angle increased significantly from 35.02 at 5100 K to 47.11 at 7200 K, indicating a perceptual color shift from red to yellowish-brown tones. In contrast, the chroma (C*) values did not exhibit any significant changes (p > 0.05). These findings emphasize the importance of standardizing illumination conditions in IPS-based color assessments and suggest that D50 (5000 K) illumination may better preserve the natural red appearance of meat than the commonly used D65 (6500 K) standard. PRACTICAL APPLICATIONS: Correlated color temperature (CCT) of the light source can affect color data. D50 illumination provides more accurate redness perception than D65 in red meat. Total color differences between CCT extremes are visually detectable.