Chen Ying, Wang Jing, Xu Liang, Nie Yuping, Ye Yunyue, Qian Jianya, Liu Fengsong, Zhang Liang
School of Food Science and Engineering, Yangzhou University, Yangzhou 225127, China.
Guangxi Key Laboratory of Clean Pulp & Papermaking and Pollution Control, School of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China.
Foods. 2024 Dec 5;13(23):3930. doi: 10.3390/foods13233930.
This study successfully developed edible films with excellent mechanical strength and notable water resistance, utilizing curdlan (CL) as the primary matrix and incorporating various plasticizers, including glycerol (GLY), ethylene glycol (EG), propylene glycol (PRO), xylitol (XY), sorbitol (SOR), and polyethylene glycol (PEG). A comprehensive suite of analytical techniques, including Fourier transform infrared spectroscopy (FTIR), wide-angle X-ray diffraction (XRD), scanning electron microscopy (SEM), dynamic mechanical analysis (DMA), and tensile testing, were employed to evaluate the films' structural and mechanical properties. After incorporating PEG, the water sensitivity increased slightly, with a contact angle (CA) of 97.6°, and a water solubility (WS) of 18.75%. The inclusion of plasticizers altered the crystalline structure of the CL matrix, smoothing and flattening the film surface while reducing hydrogen-bonding interactions. These structural changes led to a more uniform distribution of amorphous chain segments and a decrease in glass transition temperatures. Among the tested plasticizers, GLY exhibited the highest compatibility with CL, resulting in the smoothest surface morphology and delivering the most effective plasticizing effect. The CL-GLY film showed a dramatic improvement in flexibility, with an elongation at break that was 5.2 times higher than that of the unplasticized film (increasing from 5.39% to 33.14%), indicating significant enhancement in extensibility. Overall, these findings highlight the potential of CL-GLY films as sustainable and effective materials for food packaging applications.
本研究以凝胶多糖（CL）为主要基质，加入甘油（GLY）、乙二醇（EG）、丙二醇（PRO）、木糖醇（XY）、山梨醇（SOR）和聚乙二醇（PEG）等多种增塑剂，成功开发出具有优异机械强度和显著耐水性的可食用薄膜。采用了包括傅里叶变换红外光谱（FTIR）、广角X射线衍射（XRD）、扫描电子显微镜（SEM）、动态力学分析（DMA）和拉伸测试在内的一系列综合分析技术，来评估薄膜的结构和机械性能。加入PEG后，水敏感性略有增加，接触角（CA）为97.6°，水溶性（WS）为18.75%。增塑剂的加入改变了CL基质的晶体结构，使薄膜表面变得光滑和平整，同时减少了氢键相互作用。这些结构变化导致非晶链段分布更加均匀，玻璃化转变温度降低。在测试的增塑剂中，GLY与CL的相容性最高，薄膜表面形态最光滑，增塑效果最显著。CL-GLY薄膜的柔韧性有了显著提高，断裂伸长率比未增塑薄膜高5.2倍（从5.39%提高到33.14%），表明其延展性显著增强。总体而言，这些研究结果突出了CL-GLY薄膜作为食品包装应用中可持续且有效材料的潜力。
