Process method for refining neutral protease from tussah cocoon shell

Abstract

The invention relates to a process method for refining neutral protease from a tussah cocoon shell. The process method comprises the following steps of pretreatment, wherein a positive-pressure pretreatment process or a soap-alkaline pretreatment process is adopted; and neutral protease degumming, wherein 100 parts of pretreated tussah cocoon shells are prepared, the bath ratio is 1:10-15, 5-7 parts of the neutral protease (5 million units) are used, the water temperature is 40-45 DEG C, pH value is 6.5-7.5, and degumming is finished until the residual gum content of the silk fibers is detected to be 3-5%. Sericin peptide bonds of silk are removed by being broken into amino acids and polypeptide through hydrolysis in the presence of protease, fibroin is not influenced, particularly the pretreatment adopts a high-temperature and high-pressure steaming mode, the energy is saved, no chemicals contamination is caused, the refined waste silk has large tearing strength, and the fibers are fluffy, soft, glossy and have no raw and smooth cocoons; the degummed sewage water contains sericin and little neutral protease preparation, and is dehydrated through sedimentation of protein flocculating agents, and then drying is carried out to obtain sericin, and the sericin can be coarsely processed into organic fertilizers, so that the environment is improved and the social benefit is increased.

Description

technical field [0001] The invention relates to a process for degumming tussah cocoon shells, in particular to a process for degumming with neutral protease. Background technique [0002] Tussah silk is composed of sericin and silk fibroin, sericin wraps silk fibroin, silk fibroin accounts for 84%, sericin accounts for about 12%~16%, contains about 2.5% waxy pigments and inorganic substances, sericin, silk Silk fibroin is composed of protein and amino acids. Sericin is wrapped in the outer layer of silk fibroin. Normally silk spinning and weaving need to remove sericin. This degumming process is called refining. The most traditional refining method is the soap-alkali method. The principle of chemical degumming with soap is to remove sericin by utilizing the difference in stability and sensitivity of sericin and silk fibroin to alkali. Sericin is easier to be hydrolyzed and dissolved in water than silk fibroin. Removed by washing. The traditional degumming process with soap...

AI Technical Summary

Problems solved by technology

Therefore, this degumming method only makes a certain contribution to the degumming effect and reduces energy consumption. Due to the use of lye, it still causes great pollution to the environment and cannot meet the requirements of ecological, environmentally friendly and clean production.