Small-angle X-ray scattering measurements of gels produced from α-amylase-treated cassava starch granules
Small-angle X-ray scattering measurements of gels produced from α-amylase-treated cassava starch granules
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对 α-淀粉酶处理的木薯淀粉颗粒产生的凝胶进行小角 X 射线散射测量
DOI：
10.1016/j.foodhyd.2015.11.012
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发表时间：
2016
影响因子：
10.7
通讯作者：
S. Kitamura
中科院分区：
文献类型：
--
作者：
T. Ichihara;J. Fukuda;T. Takaha;S. Suzuki;Y. Yuguchi;S. Kitamura
通过来自黑曲霉的α-淀粉酶轻微水解的木薯淀粉颗粒显示出显著增强的胶凝特性（Ichihara，Fukuda，Takaha，Yuguchi，& Kitamura，2014）。本文通过动态粘弹性分析和小角X射线散射（SAXS）研究了这些增强的凝胶性能的机制。α-淀粉酶处理的木薯淀粉糊的储能模量（G′）大于天然木薯淀粉糊，在所测试的角频率下θ an δ（G″/G′）几乎为零，远低于天然木薯淀粉。小角X射线散射结果表明，微观凝胶结构是由高度聚集的不均匀的纳米级结构和单一和螺旋直链淀粉链的稀释区域。α-淀粉酶处理木薯淀粉的淀粉结晶速度和聚集体的生长速度比原淀粉快，聚集体的尺寸也比原淀粉大。这些结果进一步支持了我们的假设，即α-淀粉酶处理通过构建强的填料-基质型结构来改善淀粉凝胶的弹性。
Cassava starch granules slightly hydrolyzed by α-amylase fromAspergillus nigershow significantly enhanced gelling properties (Ichihara, Fukuda, Takaha, Yuguchi, & Kitamura, 2014). This paper investigates the mechanism of these enhanced gelling properties by dynamic viscoelastic analysis and small-angle X-ray scattering (SAXS). The storage modulus (G′)of α-amylase-treated cassava starch paste was greater than that of native cassava starch paste, and thetan δ(G″/G′)of the treated paste was almost zero at the tested angular frequency, which is much lower than for native cassava starch. The SAXS results suggest that the microscopic gel structure is composed of highly aggregated inhomogeneous nano-scale structures and diluted regions of single and helical amylose chains. Starch crystallization and growth of aggregates were faster, and the size of aggregates larger, for α-amylase-treated cassava starch than for native starch. These results further support our hypothesis that α-amylase treatment improves the elasticity of starch gel by constructing a strong filler-in-matrix type structure.