Color changes of compression and opposite spruce wood (Picea abies L. Karst.) affected by different drying conditions

The color changes of compression and opposite spruce (Picea abies L. Karst) wood were evaluated as a function of different drying conditions. Compression wood samples and their corresponding opposite wood samples from the opposite part of the log were compared after three different drying modes. The color of the samples before and after the drying was characterized using the color coordinates L*, a*, b*, C*ab, C, h*, Sab, and the color difference (ΔE*) in the standard color space according to the International Commission on Illumination (CIELAB). The drying temperature was the most remarkable factor for discoloration of the samples. The lightness (L*) of the samples decreased with increased temperature. However, darkening was more pronounced in the opposite wood samples. The overall color difference (ΔE*) was found to be higher in the opposite wood. The compression wood was more saturated in color with a deeper hue angle due to the drying process.