School of Food Science & Engineering, Yangzhou University, Huayang Xilu 196, Yangzhou, Jiangsu, 225127, People's Republic of China.
School of Hydraulic, Energy & Power Engineering, Yangzhou University, Huayang Xilu 196, Yangzhou, Jiangsu, 225127, People's Republic of China.
Carbohydr Polym. 2019 Mar 1;207:362-370. doi: 10.1016/j.carbpol.2018.12.001. Epub 2018 Dec 3.
Effect of pulsed electric field (PEF) on the structural properties of representative starches with different crystalline type, wheat starch for type A, potato starch for type B, and pea starch for type C, were investigated with polarized light microscopy (PLM), X-ray diffractometry (XRD), attenuated total internal reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, solid-state nuclear magnetic resonance (SSNMR) spectroscopy, small-angle X-ray scattering (SAXS), and gel permeation chromatography (GPC) to understand whether PEF could be applied directly in starchy foods. The results showed that PEF could change the structure of all three types of starch, especially potato starch; the birefringence, represented by Maltese cross in polarized microscopic observation changed slightly; XRD and SSNMR spectra demonstrated PEF did not change the crystalline type of starch granules. However, relative crystallinity variations happened at some points of electric field intensity (EFI). Increasing with the EFI, a bigger variation of R happened in potato starch than in wheat starch and pea starch, as illustrated by ATR-FTIR. Significant influences of PEF on the scatter structure and fractal dimension of self-similar structures were observed for wheat starch and potato starch, but not for pea starch. The GPC suggested that molecular weight distribution changed for all the three starches. And in vitro tests showed that PEF changed significantly (P < 0.05) the digestibility of starches, especially wheat starch and potato starch.
脉冲电场（PEF）对不同晶型的代表性淀粉结构特性的影响，其中包括 A 型小麦淀粉、B 型马铃薯淀粉和 C 型豌豆淀粉，通过偏光显微镜（PLM）、X 射线衍射（XRD）、衰减全内反射傅里叶变换红外（ATR-FTIR）光谱、固态核磁共振（SSNMR）光谱、小角 X 射线散射（SAXS）和凝胶渗透色谱（GPC）进行了研究，以了解 PEF 是否可以直接应用于含淀粉食品中。结果表明，PEF 可以改变三种类型淀粉的结构，尤其是马铃薯淀粉；偏光显微镜观察到的双折射，用马耳他十字表示，变化很小；XRD 和 SSNMR 图谱表明，PEF 并没有改变淀粉颗粒的结晶类型。然而，在某些电场强度（EFI）点发生了相对结晶度的变化。随着 EFI 的增加，马铃薯淀粉的 R 值变化比小麦淀粉和豌豆淀粉更大，ATR-FTIR 说明了这一点。PEF 对小麦淀粉和马铃薯淀粉自相似结构的散射结构和分形维数有显著影响，但对豌豆淀粉没有影响。GPC 表明，三种淀粉的分子量分布都发生了变化。体外试验表明，PEF 显著改变了（P<0.05）淀粉的消化率，特别是小麦淀粉和马铃薯淀粉。
