Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
Biomacromolecules. 2010 Mar 8;11(3):533-41. doi: 10.1021/bm100008p.
The unique properties of the wheat grain reside primarily in the gluten-forming storage proteins of its endosperm. Wheat gluten's structural and functional properties have led to an expanding diversity of applications in food products. However, its viscoelastic properties and low water solubility also are very interesting features for nonfood applications. Moreover, gluten is annually renewable and perfectly biodegradable. In the processing and setting of gluten containing products, temperature plays a very important role. In this review, the structure and reactivity of gluten are discussed and the importance of sulfhydryl (SH) and disulfide (SS) groups is demonstrated. Wheat gluten aggregation upon thermosetting proceeds through direct covalent cross-linking in and between its protein groups, glutenin and gliadin. Predominant reactions include SH oxidation and SH/SS interchange reactions leading to the formation of SS cross-links. Additionally, thermal treatment of gluten can result in the formation of other than SS covalent bonds. We here review two main technological approaches to make gluten-based materials: wet processes resulting in thin films and dry processes, such as extrusion or compression molding, exploiting the thermoplastic properties of proteins under low moisture conditions and potentially resulting in very useful materials. Gluten bioplastics can also be reinforced with natural fibers, resulting in biocomposites. Although a lot of progress has been made the past decade, the current gluten materials are still outperformed by their synthetic polymer counterparts.
小麦颗粒的独特性质主要存在于其胚乳中的形成面筋的储存蛋白中。小麦面筋的结构和功能特性使其在食品产品中的应用不断多样化。然而，其黏弹性和低水溶性也是非食品应用非常有趣的特性。此外，面筋是每年可再生且完全可生物降解的。在含有面筋的产品的加工和设置过程中，温度起着非常重要的作用。在这篇综述中，讨论了面筋的结构和反应性，并说明了巯基（SH）和二硫键（SS）基团的重要性。面筋在热固性聚合过程中通过其蛋白质组（麦谷蛋白和醇溶蛋白）之间和内部的直接共价交联进行聚集。主要反应包括 SH 氧化和 SH/SS 交换反应，导致 SS 交联的形成。此外，面筋的热处理会导致形成除 SS 共价键以外的键。我们在这里回顾了两种制造基于面筋的材料的主要技术方法：湿处理导致薄膜形成和干处理，例如挤出或压缩成型，利用蛋白质在低水分条件下的热塑性特性，并可能产生非常有用的材料。面筋生物塑料也可以用天然纤维增强，形成生物复合材料。尽管过去十年取得了很多进展，但目前的面筋材料仍然不如其合成聚合物材料性能优越。
