热软化及干燥处理对棕榈藤材色的影响

The Effect of Softening and Drying Process on Rattan Color

通过汽蒸和微波加热方式对云南省藤、 版纳省藤和高地钩叶藤进行软化并用传统烘箱和微波加热对藤材进行干燥,测定其色度学参数变化,评价热软化和干燥过程对藤材材色的影响.结果表明：藤材明度（L＊）明显降低,色调角（ΔAg＊）均为负值,饱和度（C＊）下降,色差（ΔE＊）为18-30,汽蒸软化方式对藤材明度（L＊）及色差（ΔE＊）的影响大于微波软化处理;藤材的干燥过程是明度逐渐增加的过程,但干燥处理对藤材表面明度的影响仍小于软化处理对藤材表明明度的影响;经干燥处理的3种藤材材色的饱和度增加,色调角改变,出现一定程度的偏红和偏蓝变化.在同一干燥介质、 温度条件下,藤材色差随干燥时间的增加逐渐减小;在同一干燥介质条件下,较高温度条件下完成干燥的藤材色差大于该藤种在低温条件下干燥完成后的色差;经干燥后的3种藤材色差均小于藤材软化前后色差值,干燥过程有助于减少材色差异,其中以微波干燥方式效果更为显著.

Calamus yunnanensis, C. nambaruensis and Plectocomia himalayana were softened by microwave and steaming heating, using traditional oven and microwave heating to dry the rattan. The changes of color parame-ters were determined, and the effect of the softening and drying process on the rattan color was evaluated. The re-sults showed that the brightness （ L＊） and saturation （ C＊） of softening rattan samples decreased, hue angle （ΔAg＊） was minus, chromatic aberration （ΔE＊） was in the range of 18-30. The effect of steam softening method on L＊ and ΔE＊ was more obviously than microwave. The L＊ gradually increased in the process of drying, but the effect of drying process on L＊ was lower than that of softening process. The C＊ of 3 dried samples increased and Ag＊ changed, the rattan color appeared slight red and blue. ΔE＊ gradually decreased as drying time increasing in the same medium temperature. ΔE＊ of rattan samples drying by higher medium temperature were more obvious than that with lower medium temperature.ΔE＊ of 3 rattan samples after drying was smaller than that before and after softening, The drying process contributed to rattan color difference reducing, and microwave drying process was more significant.