牛蒡蛋白的提取与功能特性研究 毕业论文.doc

图书分类号： 密 级： 毕业设计(论文) 牛蒡蛋白的提取与功能特性研究 STUDY ON THE EXTRACTION AND FUNCTIONAL CHARACTERISTICS OF PROTEIN FROM THE BURDOCK 学生姓名 学院名称 食品（生物）工程学院 专业名称 食品科学与工程 指导教师  2010年 6月 10日 摘要 本实验以干燥脱水牛蒡为原料，用考马斯亮蓝比色法测定蛋白质的含量，在牛蒡蛋白的等电点测定的基础上，采用碱提酸沉法提取牛蒡蛋白，分别研究pH、温度、料液比、时间对牛蒡蛋白质得率的影响，确定了牛蒡蛋白质提取的最佳工艺参数。结果表明：牛蒡蛋白的等电点pI=4.5，牛蒡蛋白提取的最佳工艺参数为pH=9、T=40℃、料液比=1∶25、时间=50min，其得率为5.82%。进一步研究分析了牛蒡蛋白质的功能特性，并与大豆蛋白进行了比较，结果表明：牛蒡蛋白的溶解性高于大豆蛋白，牛蒡蛋白的保水性、乳化活性和乳化稳定性、吸油性、起泡性和起泡稳定性均稍低于大豆蛋白，粘度两者差不多，凝胶性当两者浓度为8%以上时能形成凝胶。 关键词 牛蒡；等电点；蛋白质提取；功能特性 Abstract This article select the experimental dehydration drying fresh burdock，with Coomassie brilliant blue colorimetric determination of protein content and burdock protein isoelectric point, using alkaline extraction acid burdock extract protein, to study the pH, temperature, liquid ratio, time burdock rate of protein extract to determine protein burdock Extraction of the best process parameters. Analysis showed that：burdock protein isoelectric point pI = 4.5, burdock extract protein for the best process parameters pH = 9, T = 40 ℃, liquid ratio = 1:25, time = 50min, the extraction rate of 5.82% . Burdock further analysis of the functional properties of protein and soy protein compared. The results show that the burdock features in protein solubility of soy protein than the high water-holding capacity of soy protein is superior to protein burdock, emulsifying activity and emulsion stability of soybean protein is slightly higher than burdock protein, soy protein is slightly higher than the absorption of protein burdock, foaming and foaming stability of soybean protein is slightly higher than the protein burdock, almost two viscosity, gel concentration and when the two are more than 8% gel can form. Keywords: Burdock Isoelectric point Protein extraction Features  目 录 1 绪论 1 1.1牛蒡蛋白研究的意义 1 1.1.1牛蒡简介 1 1.1.2牛蒡的营养价值 3 1.1.3牛蒡的化学成分及药用价值 3 1.1.4牛蒡用于食品加工的现状 3 1.1.5牛蒡蛋白 3 1.2牛蒡蛋白的功能特性 3 1.3本课题的研究目的和意义 4 2 材料与方法 5 2.1实验材料与设备 5 2.1.1 主要材料及试剂 5