CSIRO, Materials Science and Engineering, Clayton, Vic. 3169, Australia.
Carbohydr Polym. 2013 Jun 20;95(2):649-53. doi: 10.1016/j.carbpol.2013.03.045. Epub 2013 Mar 21.
The well recognized complex issue of compatibility between starch and gelatin was investigated based on their interface and phase composition using synchrotron FTIR micro-spectroscope. A high amylose (80%) corn starch grafted with flexible and hydrophilic hydroxpropyl groups and plasticized by poly(ethylene glycol) (PEG) was used in this work. The FTIR beam focused on a 5 μm×5 μm detection region and the micro-spectroscope was scanned across the gelatin-starch interface. It was found that there was about a 20 μm thickness layer where gelatin and starch were in co-existence, indicating that gelatin and starch are compatible to a certain degree in this system. The ratio of the areas of the saccharide CO bands (1180-953 cm(-1)) and the amide I and II bands (1750-1483 cm(-1)) was used to monitor the relative distributions of the two components of the blends. FTIR 2 and 3-dimensional maps indicated that gelatin constituted the continuous phase up to 80% of starch content. The PEG was homogeneously distributed in both gelatin and starch phases, and blurred the interface between gelatin and starch in the chemical maps, indicating that PEG acted not only as a plasticizer but as a compatibilizer for the gelatin-starch blends.
利用同步辐射傅里叶变换红外显微镜（FTIR 微光谱仪），基于淀粉和明胶的界面和相组成，研究了两者之间公认的相容性这一复杂问题。本研究使用了经柔性亲水性羟丙基接枝改性、并用聚乙二醇（PEG）增塑的高直链玉米淀粉（直链淀粉含量 80%）。FTIR 光束聚焦在 5μm×5μm 的检测区域，微光谱仪在明胶-淀粉界面上进行扫描。结果发现，约有 20μm 厚的层中同时存在明胶和淀粉，表明在该体系中明胶和淀粉在一定程度上是相容的。用糖 CO 带（1180-953cm(-1)) 和酰胺 I 和 II 带（1750-1483cm(-1))的面积比来监测混合物中两种成分的相对分布。FTIR 二维和三维图谱表明，明胶构成了连续相，直到淀粉含量达到 80%。PEG 在明胶和淀粉相中均匀分布，并在化学图谱中模糊了明胶和淀粉之间的界面，表明 PEG 不仅作为增塑剂，而且作为明胶-淀粉共混物的增容剂。
