Raschip Irina Elena, Fifere Nicusor, Lazar Maria Marinela, Hitruc Gabriela-Elena, Dinu Maria Valentina
"Petru Poni" Institute of Macromolecular Chemistry, Grigore Ghica Voda Alley 41A, 700487 Iasi, Romania.
Gels. 2023 Jun 29;9(7):528. doi: 10.3390/gels9070528.
The use of polysaccharides with good film-forming properties in food packaging systems is a promising area of research. Xanthan gum (XG), an extracellular polysaccharide, has many industrial uses, including as a common food additive (E415). It is an effective thickening agent, emulsifier, and stabilizer that prevents ingredients from separating. Nevertheless, XG-based polymer films have some disadvantages, such as poor mechanical properties and high hydrophilic features, which reduce their stability when exposed to moisture and create difficulties in processing and handling. Thus, the objective of this work was to stabilize a XG matrix by cross-linking it with glycerol diglycidyl ether, 1,4-butanediol diglycidyl ether, or epichlorohydrin below the freezing point of the reaction mixture. Cryogelation is an ecological, friendly, and versatile method of preparing biomaterials with improved physicochemical properties. Using this technique, XG-based cryogels were successfully prepared in the form of microspheres, monoliths, and films. The XG-based cryogels were characterized by FTIR, SEM, AFM, swelling kinetics, and compressive tests. A heterogeneous morphology with interconnected pores, with an average pore size depending on both the nature of the cross-linker and the cross-linking ratio, was found. The use of a larger amount of cross-linker led to both a much more compact structure of the pore walls and to a significant decrease in the average pore size. The uniaxial compression tests indicated that the XG-based cryogels cross-linked with 1,4-butanediol diglycidyl ether exhibited the best elasticity, sustaining maximum deformations of 97.67%, 90.10%, and 81.80%, respectively.
在食品包装系统中使用具有良好成膜性能的多糖是一个很有前景的研究领域。黄原胶（XG）是一种细胞外多糖，有许多工业用途，包括作为一种常见的食品添加剂（E415）。它是一种有效的增稠剂、乳化剂和稳定剂，可防止成分分离。然而，基于XG的聚合物薄膜有一些缺点，如机械性能差和高亲水性，这会降低其在接触水分时的稳定性，并在加工和处理方面造成困难。因此，这项工作的目的是通过在反应混合物的冰点以下将XG基质与甘油二缩水甘油醚、1,4-丁二醇二缩水甘油醚或环氧氯丙烷交联来使其稳定。冷冻凝胶化是一种生态友好且通用的制备具有改善物理化学性质的生物材料的方法。使用这种技术，成功制备了微球、整块材料和薄膜形式的基于XG的冷冻凝胶。通过傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）、原子力显微镜（AFM）、溶胀动力学和压缩试验对基于XG的冷冻凝胶进行了表征。发现了一种具有相互连接孔隙的异质形态，平均孔径取决于交联剂的性质和交联比。使用大量交联剂会导致孔壁结构更加致密，平均孔径显著减小。单轴压缩试验表明，与1,4-丁二醇二缩水甘油醚交联的基于XG的冷冻凝胶表现出最佳弹性，分别能承受97.67%、90.10%和81.80%的最大变形。
