Effects of alkaline-soluble okra gum on rheological and thermal properties of systems with wheat or corn starch
Effects of alkaline-soluble okra gum on rheological and thermal properties of systems with wheat or corn starch
复制标题
DOI：
10.1016/j.foodhyd.2012.07.003
复制
发表时间：
2013-03-01
影响因子：
10.7
通讯作者：
Hussain, Shahzad
中科院分区：
文献类型：
--
作者：
Alamri, Mohammed S.;Mohamed, Abdellatif A.;Hussain, Shahzad
采用快速粘度分析仪（RVA）、Brookfield粘度计、差示扫描量热仪（DSC）和光学显微镜研究了黄秋葵提取物（OE）对小麦淀粉和玉米淀粉流动性质和热性质的影响。通过替代5、10、15%的淀粉来制备淀粉-OE共混物。RVA数据表明，相对于对照，OE降低了两种淀粉的峰值粘度。这是预期的，因为被OE取代的淀粉量减少。然而，淀粉回缩的下降不仅仅是共混物中省略的淀粉。共混物的DSC扫描数据显示与对照相比更高的峰值温度，表明在OE存在下淀粉颗粒糊化较慢。（在50 ℃下进行）证明了剪切应力作为剪切速率的函数增加，但是在高OE含量下，共混物的剪切应力显示出抗改变性，这通过在较高OE含量下作为剪切速率的函数的较低的剪切应力斜率来证实。总体而言，可以得出结论，OE影响了淀粉的研究性质，无论是通过间接控制水的运动，或通过与直链淀粉的相互作用，如淀粉凝胶挫折的结果。(C)2012爱思唯尔有限公司保留所有权利。
The effect of okra extract (OE) on the flowing and thermal properties of wheat and corn starch was investigated using rapid visco-analyzer (RVA), Brookfield viscometer, differential scanning calorimetry (DSC), and light microscopy. Starch-OE blends were prepared by replacing 5, 10, 15% of the starch. The RVA data showed that OE reduced the peak viscosity of both starches relative to the control. That was expected because of the reduction in the amount of starch that was replaced by OE. However, the drop in starch setback was more than just the omitted starch in the blend. The DSC scan data of the blends showed higher peak temperature compared to the control, indicating slower starch-granules gelatinization in the presence of OE. Brookfield profiles (performed at 50 degrees C) demonstrated increase in shear stress as a function of shear rate, but at high OE content, the shear stress of the blends showed resistant to change which was confirmed by lower slope of shear stress as a function of shear rate at higher OE content. Overall, it can be concluded that OE has influenced the investigated properties of the starches, either by indirectly controlling water movement, or by interacting with amylose as indicated by starch-gel setback outcome. (C) 2012 Elsevier Ltd. All rights reserved.