INFRARED-SPECTRA AND DIELECTRIC-PROPERTIES OF THERMALLY TREATED SOYBEAN PROTEINS

被引：13

作者：

MOHARRAM, MA ^{[1
]}

ABDELNOUR, KN ^{[1
]}

ABDELRAOF, G ^{[1
]}

机构：

[1] NATL RES CTR,DEPT MICROWAVE PHYS,CAIRO,EGYPT

来源：

POLYMER DEGRADATION AND STABILITY | 1994年 / 45卷 / 03期

关键词：

D O I：

10.1016/0141-3910(94)90214-3

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

The infrared spectra of protein, heat-treated at various temperatures and times in the atmosphere were recorded. The temperature-induced changes in the absorbance of the bands at 1660, 1530 and 2950 cm(-1) were determined. The data revealed that soybean protein exhibits significant breakdown on heating at 90 degrees C as indicated by the marked decrease in the absorbances of C-O and C-H stretching vibrations and the N-H bending vibration, in addition to the significant decrease in the permittivity epsilon' and dielectric loss epsilon''. The decrease exhibited after heating above 100 degrees C can be attributed to the NH groups and a decrease in the amount of amide groups. Moreover the degradation of soybean protein molecules to lower molecular weight substances takes place on heating above 160 degrees C. The effect of water content on epsilon' and epsilon'' of soybean protein was also investigated. It was concluded that the DC conductivity depends upon water content while there is no detectable dependency on increasing temperature.

引用

页码：429 / 434

页数：6

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