The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, The Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China.
The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, The Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China.
Food Res Int. 2017 Oct;100(Pt 1):180-192. doi: 10.1016/j.foodres.2017.07.001. Epub 2017 Jul 3.
To investigate the characteristics of chemically modified wheat starch, such as oxidized (OWS), cross-linked (CLWS) and dual-modified wheat starches, cross-linked oxidized (COWS) and oxidized cross-linked (OCWS) wheat starches were obtained by 12% hydrogen peroxide (HO) and 2% sodium phytate treatments, respectively. After modifications of wheat starch by cross-linking and oxidization, it was determined that native wheat starch was effectively modified with respect to the structure and physicochemical characteristics, as detected by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), Rapid Visco Analyzer (RVA), scanning electron microscopy (SEM) and X-ray diffraction (XRD). DSC analysis demonstrated that peak temperature (T) 64.41°C of the COWS was the highest. The RVA viscosity indexes of CLWS were noticeably increased compared with the other four starches, of which three oxidized starch samples showed lower RVA profiles because of oxidation. The XRD result indicated that cross-linked phosphates from sodium phytate were primarily located in the amorphous regions of starch granules. After modifications by different treatments, the starch samples exhibited different morphological characteristics, including A-type and B-type wheat starch granules, which showed much closer contact with each other by the cross-linking reaction under SEM observations. The functional characteristics, including solubility, swelling power, light transmittance and freeze-thaw stability (FTS), of all five treated and untreated wheat starches demonstrated that COWS had the highest solubility at 0.57 and that CLWS showed the best swelling power at 12.63 (g/g). The paste clarity of COWS was improved to 47.72% higher than that of native starch (7.54%), and the water loss of COWS (21.62%) was the lowest, which is beneficial to the production of quick-frozen food. Our results showed that dual-modified starch by using sodium phytate and hydrogen peroxide had significantly altered structural and functional properties. The present study provides fundamental information of dual-modified wheat starch for its potential industrial application.
为了研究化学改性小麦淀粉的特性，如氧化（OWS）、交联（CLWS）和双改性小麦淀粉（COWS）和氧化交联（OCWS）小麦淀粉，分别用 12%的双氧水（HO）和 2%的植酸钠处理得到。通过对小麦淀粉进行交联和氧化改性后，傅里叶变换红外光谱（FT-IR）、差示扫描量热法（DSC）、快速黏度分析仪（RVA）、扫描电子显微镜（SEM）和 X 射线衍射（XRD）检测到，天然小麦淀粉的结构和物理化学特性得到了有效改性。DSC 分析表明，COWS 的峰值温度（T）为 64.41°C，最高。与其他四种淀粉相比，CLWS 的 RVA 黏度指数明显增加，其中三种氧化淀粉样品由于氧化作用，RVA 图谱较低。XRD 结果表明，植酸钠中的交联磷酸主要位于淀粉颗粒的无定形区。经过不同处理的改性后，淀粉样品表现出不同的形态特征，包括 A 型和 B 型小麦淀粉颗粒，通过 SEM 观察到交联反应使它们彼此之间的接触更加紧密。所有五种处理和未处理的小麦淀粉的功能特性，包括溶解度、膨胀力、透光率和冻融稳定性（FTS），表明 COWS 的溶解度最高，为 0.57，CLWS 的膨胀力最好，为 12.63（g/g）。COWS 的糊透明度提高到 47.72%，比原淀粉（7.54%）高，COWS 的水分损失（21.62%）最低，有利于速冻食品的生产。研究结果表明，用植酸钠和双氧水双改性淀粉显著改变了其结构和功能特性。本研究为其潜在的工业应用提供了双改性小麦淀粉的基础信息。
