低场核磁共振法测定热烫面团水分迁移特性及超微结构分析

本实验采用低场核磁共振技术，研究水温和加水量对热烫面团中的水分分布和水分迁移特性的影响，并对其微观结构进行扫描电镜分析。结果表明：随着加水量的增加，热烫面团结合水和表面自由水的含量下降，吸附水含量增加；随着水温的升高，热烫面团结合水含量先升高后降低，吸附水和表面自由水的含量先降低后升高；超微结构图显示水温对面团微观结构影响较大，淀粉出现糊化现象，使得面团更加均匀细腻；水量的增加使得淀粉颗粒与面筋结构更多地黏连在一起，空隙也随之变小。

Moisture Migration and Ultrastructure of Hot-Water Dough as Studied with LF-NMR and SEM

The effects of water temperature and water to flour ratio on moisture distribution and transfer characteristics in
hot-water dough were studied using low-field nuclear magnetic resonance (LF-NMR), and the ultrastructure of the dough
was observed under scanning electron microscope (SEM). The results showed that the bound and free water contents in hotwater
dough decreased and the adsorbed water content increased with an increase in water to flour ratio. Increasing water
temperature resulted in an initial increase followed by a decrease in the bound water content but the opposite changes in the
adsorbed and free water contents in hot-water dough. The ultrastructure was affected greatly by water temperature, and the
surface of the dough became more uniform and smooth as a result of starch gelatinization. The starch particles were tightly
stuck with gluten structure and their voids consequently became smaller with an increase in water to flour ratio.