从营口对虾虾壳制备壳聚糖的研究

Study on Preparation of Chitosan from Yingkou Shrimp Shell

以营口本地对虾虾壳为原料,用稀HCI和NaOH溶液分别脱去钙和蛋白质及脂肪得到甲壳素样品,使用浓碱加热处理得到壳聚糖。通正交试验设计计优化了壳聚糖的制备过程。结果表明壳聚糖制备的最佳条件是先用稀酸脱盐,再用稀碱脱蛋白得到甲壳素,随后用45%NaOH溶液,在95℃、反应时间6 h下得到壳聚糖。自制壳聚糖与市售壳聚糖的红外光谱图一致。用酸碱滴定法和红外光谱法分别测定了样品的脱乙酰度。重量法测定壳聚糖的水分。乌氏粘度计测定壳聚糖大的平均相对分子质量。所得壳聚糖的水分含量为14%,脱乙酰度为74%,平均相对分子质量为4.30×10^(4)。

In this paper,the shrimp shells of Yingkou local shrimp were used as raw materials,and the calcium,protein and fat were removed with dilute HCI and NaOH solutions respectively to obtain chitin,which were then heated with concentrated alkali to prepare chitosan.The preparation of chitosan was optimized by orthogonal experimental design.The results showed that the best condition for preparation of chitosan was to firstly desalt with dilute acid,then deproteinize with dilute alkali.Chitosan was prepared by deacetylation of chitin,which is completed by reacting for 6h at 95℃in 45%NaOH solution.The infrared spectrum of the obtained chitosan is consistent with that of commercially available chitosan.The degree of deacetylation of the samples was determined by acid-base titration and infrared spectroscopy.The moisture content of chitosan was determined by gravimetric method.The average molecular weight of chitosan was measured by Ubbelohde viscometer.The water content of the obtained chitosan is 14%.The degree of deacetylation is 74%with the average molecular weight of 4.30×10^(4).