小麦遗存是研究早期人类粮食种类的重要植物考古材料。出土的小麦遗存大多数都已经炭化，但对于炭化的环境和条件尚不清楚。通过室内炭化实验在不同温度条件下对现代小麦进行烘烤，研究小麦的质量、表面颜色和粉末颜色随时间的变化来揭示小麦遗存形成的炭化条件。200 ℃以下的小麦质量和颜色变化较小，250 ℃及以上小麦的质量和颜色变化较大，且有内容物溢出。在200 ℃以下小麦的质量变化主要由于失水造成，而250 ℃以上的质量变化，不仅有水分的失去还有大量有机物、无机物等的失去。在不同的温度条件下，小麦的表面颜色与粉末颜色的L*值（亮度或者白度）变化几乎同步，两者的a*值（红-绿彩度）和b*值（黄-蓝彩度）变化不同步，但a*值和b*值的变化趋势相似。虽然样品起始时表面颜色和粉末颜色的值不同，当小麦完全炭化后，表面颜色和粉末颜色的值几乎相同。实验模拟结果表明不同的温度下小麦炭化的质量损失量、颜色变化不同，为理解炭化小麦形成的条件提供一定的参考信息。
关键词：
植物考古; 小麦; 炭化; 质量; 颜色
The remains of wheat are important paleoethnobotany materials for studying the early types of human food. Most of the remains of unearthed wheat have been carbonized, but the conditions for carbonization are not clear. The indoor carbonization experiments were conducted under different temperature conditions by baking modern wheat to study the changes in wheat mass, surface color, and powder color with time, in order to reveal the carbonization conditions for the wheat remains. The mass and color changes of wheat under 200℃ were relatively small, and the mass and color of wheat varied greatly at 250℃ and above.At temperatures below 200℃, the main changes in the mass of wheat were caused by the loss of water. At temperatures above 250℃, there were significant losses of organic and inorganic substances besides the loss of water. Under different temperature conditions, the changes in L* values (light or white) of wheat surface color and powder color were nearly synchronous, and the changes in a* values (red-green) and b* values (yellow-blue) were asynchronous. The change tendencies for the a* value and b* value were similar. Although the values of the colors of the surface and the powder were different at the beginning of the experiment, the values of wheat surface color and powder color were almost the same when wheat was completely carbonized. Experimental simulation results show the mass losses and color changes in wheat carbonization at different temperatures and provide valuable information for understanding the formation of carbonized wheat.
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