关键词: LF-NMR, 差示扫描量热仪, 水分状态, 玻璃化转变, 微观结构

Abstract: Emulsifiers can affect the textural structure and glass transition temperature (Tg) of dough by changing its water state. In this study, the effect of five emulsifiers on water state in dough was by using LF-NMR. Meanwhile, DSC and SEM were used to analyze their effect on the Tg and microstructure after low-temperature storage of dough, respectively. The results showed that emulsifiers could decrease the proportion of free water in dough. The addition of 0.15% DATEM resulted in a 5.78% decrease in free water. In addition, emulsifiers also caused changes in the Tg of dough. Moreover, the Tg of dough with the addition of 0.50% glyceryli monostearici was －17.3 ℃, and revealed an increase of 14 ℃ compared with blank dough. However, the addition of SP60 or lecithin did not cause a significant increase in the Tg of dough. Furthermore, emulsifiers improved the textural structure of frozen dough to different extent. Glass-state storage of frozen dough was achieved by adding 0.50% glyceryli monostearici or 0.15% DATEM and the textural structure of frozen dough was well protected.

Key words: LF-NMR, DSC, water state, glass transition temperature, textural structure