基于X射线衍射和低场核磁共振技术的微波膨胀烟梗收缩机制  

Study on the contraction mechanism of microwave expanded tobacco stem based on XRD and LF-NMR techniques

作　　者：李晓 王巍 袁帅 韩明 赵子龙 姚光明[4] LI Xiao;WANG Wei;YUAN Shuai;HAN Ming;ZHAO Zilong;YAO Guangming(College of Food and Bioengineering,Zhengzhou University of Light Industry,Zhengzhou 450001,China;Anyang Cigarette Factory of Henan Pvovince,Anyang 455004,China;Changde Cigarette Factory of Hunan Province,Changde 415000,China;Zhengzhou Tobacco Research Institute of CNTC,Zhengzhou 450001,China)

机构地区：[1]郑州轻工业大学食品与生物工程学院,郑州450001 [2]河南省安阳卷烟厂,河南安阳455004 [3]湖南省常德卷烟厂,湖南常德415000 [4]中国烟草总公司郑州烟草研究院,郑州450001

出　　处：《扬州大学学报（农业与生命科学版）》2022年第2期127-134,共8页Journal of Yangzhou University：Agricultural and Life Science Edition

基　　金：河南省科技攻关项目(142102210639)。

摘　　要：利用XRD和LF-NMR技术,研究不同微波功率对烟梗内部晶体及纤维饱和点的影响,分析微波膨胀烟梗回潮前后收缩过程的变化情况,研究微波膨胀烟梗回潮后收缩与其内部因素的关系。结果表明:(1)随着微波功率的增大,烟梗膨胀后的体积和回潮后的收缩率均有所增大,而烟梗回潮后的体积则先减小后增大,且当微波功率为640 W时,烟梗回潮后的体积最大。其主要原因是当微波功率较高时,烟梗的内部结构及纤维素分子链发生变化。(2)微波处理不会改变烟梗纤维内部晶体结构,而是主要作用于无定形区,并且使无定形区的面积增大,进而结晶区的相对含量减少,最终导致结晶度降低。(3)随着烟梗结晶度的减小,纤维之间的结合程度变疏松,游离羟基增多,烟梗吸湿能力增强,进而导致含水率以及收缩率均明显增加。(4)随着微波功率的增加,微波膨胀烟梗的绝对含水率及纤维饱和点均逐步增加。(5)微波膨胀烟梗回潮后收缩率受纤维饱和点影响显著,两者呈正相关关系。In order to explore the shrinkage of microwave expanded tobacco stem during the rejuvenation process, XRD and LF-NMR techniques were used to study the effect of different microwave power on the saturation point of crystals and fibers in the tobacco stem, analyze the changes of the volume of expanded tobacco stem before and after rejuvenation, and clarify the relationship between the volume of expanded tobacco stem after rejuvenation and the structures of tobacco stem. The results showed that:(1) With the increase of microwave power, the volume of expanded tobacco stems and the shrinkage rate after conditioning both increased, while the volume of the tobacco stems after conditioning decreased first and then increased. And the tobacco stems had the largest volume after conditioning when the microwave power was at 640 W which indicated that when the microwave power was relatively high, the internal structure and the cellulose molecular chain of the tobacco stems changed.(2) Microwave treatment did not change the internal crystal structure of tobacco stem fibers, but mainly acted on the amorphous region, and increases the area of the amorphous region. Then the relative content of the crystalline decreased, which ultimately led to a decrease in crystallinity.(3) As the crystallinity of the tobacco stems decreased, the extent of Integration between the fibers became loose, and free hydroxyl groups increased.Therefore,the moisture absorption capacity of the tobacco stems increased,which in turn caused a significant increase in both the moisture content and the shrinkage ratio.(4) With the increase of microwave power,the absolute moisture content and fiber saturation point of the microwave expanded tobacco stems gradually increased.(5) The shrinkage ratio of the microwave expanded tobacco stems after conditioning was significantly affected by the fiber saturation point,and there was a positive correlation between them.

关 键 词：微波膨胀烟梗 收缩机制 结晶度 纤维饱和点 收缩率 

分 类 号：TS452.2[农业科学—烟草工业]