The degumming of silk and the recovery of sericin from wastewater can be performed in different ways. In this study, the quantity and quality of silk sericin from mulberry silkworms are evaluated through four degumming methods: the alkaline, the hot water, the high temperature and high pressure (HTHP) and the microwave methods. The sericin powders obtained were rigorously characterized through the elementary composition, Scanning Electron Microscopy (SEM), spectroscopy (UV, IR and fluorescence), secondary structure, thermal stability, molecular weight analysis, and compared to a commercial sericin. The results demonstrate that microwave is the most effective degumming method because all of the sericin contained in the cocoons is recovered. It was shown that sericin samples obtained by different extraction methods have similar composition. However, differences were observed in the chain length of sericin samples. The molecular weights of sericin are high for alkaline and microwave degumming and lower molecular weights are observed for sericin from hot water and HTHP degumming. The analysis of the secondary structure confirms that sericin is highly structured in aggregated or in β sheet conformation. The morphology and the structural organization of the sericin can be altered from one extraction to another, modifying sericin properties.

丝绸的脱胶和从废水中回收丝胶可以以不同的方式进行。本研究通过碱法、热水法、高温高压法和微波法四种脱胶方法对桑蚕丝胶的数量和质量进行了评价。获得的丝胶粉末通过元素组成、扫描电子显微镜 (SEM)、光谱学（UV、IR 和荧光）、二级结构、热稳定性、分子量分析进行了严格表征，并与商业丝胶蛋白进行了比较。结果表明，微波是最有效的脱胶方法，因为蚕茧中的丝胶被全部回收。结果表明，通过不同提取方法获得的丝胶样品具有相似的成分。然而，丝胶样品的链长存在差异。对于碱性脱胶和微波脱胶，丝胶的分子量较高，而热水和高温高压脱胶的丝胶分子量较低。二级结构分析证实丝胶蛋白高度结构化，呈聚集或β折叠构象。从一种提取物到另一种提取物，丝胶蛋白的形态和结构组织可以改变，从而改变丝胶蛋白的性质。