不同产地C3F烟叶色域、底色和色差的量化分析

为精确量化不同产地烟叶在色域、底色和色差等烟叶颜色质量指标上的特征,采用L^*a^*b^*颜色空间表征方法对4个植烟区烤烟C3F烟叶表面颜色进行量化分析。结果表明:(1)不同产地烤烟表面颜色具有明显差异,尤其色域和底色差异较大;(2)不同色域烟叶在颜色量化指标上有显著差异,烤烟C3F烟叶随着色域颜色加深,明度L^*和黄度b^*逐渐降低,红度a~*逐渐增大;(3)不同底色烟叶在颜色量化指标上有显著差异,微红底色烟叶明度L^*和黄度b^*较小;(4)烟叶叶面和叶背之间具有较大色差,色差值分布于5.10~8.67。烟叶叶尖与叶基色差分布值在0.50~4.16,叶基与叶中色差值分布于0.29~2.27。外观判断颜色结果与其对应的颜色值状态基本吻合,结合烟叶颜色值和外观评价能更精确地量化不同烟叶在色域、底色和色差上的差异。

Quantitative Analysis of Color Gamut,Background Color,Color Difference of C3F Grade Tobacco Leaves from Different Tobacco Growing Areas

In order to accurately quantify the characteristics of color quality indices of tobacco leaves from different areas,such as gamut,background color and color difference,the surface color of flue-cured tobacco C3 F leaves from four tobacco growing areas was quantitatively analyzed by L^*a^*b^*color space characterization method.The results showed that:(1) The surface color of flue-cured tobacco from different producing areas has obvious difference,especially the color gamut and background color;(2) there was significant differences in color quantification indexes among different color gamut tobacco leaves.With the deepening of color gamut,lightness L^* and yellowness b^* of flue-cured tobacco C3 F tobacco decreased gradually,and redness a^* increased gradually;(3) there were significant differences in color quantification indices among tobacco leaves with different background colors.The lightness L^* and yellowness b^* of tobacco leaves with reddish background colors were smaller than those of tobacco leaves with reddish background colors;(4) the color difference between leaf surface and back of tobacco leaves was larger,and the value of color difference was 5.10-8.67.Distribution of leaf tip-leaf color difference was 0.50-4.16,and that of leaf base-leaf color difference was 0.29-2.27.The results of color judgment by appearance basically coincide with the corresponding color values.Combining with the color values and appearance evaluation of tobacco leaves,the differences of color gamut,background color and color difference of different tobacco leaves can be quantified more accurately.