食品科学论文编号:SP126  论文字数:7350,页数:21

目  录
中文摘要 I
英文摘要 II
目录 III
1.  绪论 1
1.1  茶叶 1
1.2  茶叶蛋白. 1
1.2.1  茶叶蛋白的组成. 1
1.2.2  茶叶蛋白的提取方法. 2
1.3  国内茶叶蛋白的研究情况. 3 
1.4  本课题的研究内容和意义 3
2.  实验部分 4
2.1  实验材料 4
2.2  主要试剂 4
2.3  主要仪器和设备 4
2.4  实验方法 4
     2.4.1  碱法提取茶叶蛋白 4
     2.4.2  持水性 5
     2.4.3  吸水性 5
     2.4.4  乳化性及乳化稳定性 5
     2.4.5  吸油性 5
     2.4.6  起泡性和泡沫稳定性 5
     2.4.7  凝胶性 6
     2.4.8  溶解性 6
     2.4.9  SDS—电泳分析茶叶蛋白分子量的分布 7
     2.4.10  氨基酸组成和含量 7
     2.4.11  双向电泳分析相对分子量 7

3. 结果与讨论 8
3.1  蛋白质提取结果 8
3.2  标准蛋白质溶解曲线 8
3.3  茶叶蛋白溶解性曲线 8
3.4  两种茶叶蛋白功能性质比较  9                    
3.5  SDS—电泳分析茶叶蛋白分子量的分布 10 

    3.6  氨基酸组成和含量 12                            
 3.7  双向电泳分析相对分子量 13                                        
4．总结与展望 16
致谢 17
参考文献 18

摘 要：茶是最受人们欢迎的健康饮料之一,茶叶中含有茶蛋白、茶多酚、茶多糖和咖啡碱。我国在提高茶叶产量、茶叶质量及提取茶叶有效成分等方面进行了大量的研究工作，取得了重要成果。在茶叶蛋白方面的研究也取得了一些初步的研究，本课题研究的是茶叶蛋白相关的功能性质。采用碱法分别提取茶叶蛋白和茶叶鲜蛋白,对两种蛋白的溶解性、分子量、氨基酸成分、吸水性、持水性、吸油性、乳化性、乳化稳定性、起泡性、凝胶性等功能性质进行了研究。结果表明干茶叶蛋白的吸油性、凝胶性和乳化性比新鲜茶叶蛋白好，而溶解性、吸水性、乳化稳定性、起泡性和起泡稳定性不如新鲜茶叶蛋白。对两种茶叶蛋白的分子量分布和氨基酸成分也做了研究，结果蛋白质组分差异不大,茶叶蛋白各条区带的分子量大小差别较小；氨基酸成分则是除半胱氨酸是新鲜茶叶蛋白含量稍高点，其它氨基酸成分都是干茶叶蛋白含量高。并从营养性、功能性方面综合评价茶叶蛋白的开发价值及在食品中的应用前景。

关键词：茶叶蛋白；碱法；功能性质；氨基酸分析；双向电泳

Abstract: The tea is one of the most popular healthy drinkables, it includes tea protein, tea polysaccharide, tea polysaccharide and coffee pot. Tea protein was extracted using alkaline method form fired and fresh tea, respectively, then the solubility, molecular weights, amino acids composition, water absorption, oil absorption, emulsion capacity, emulsion stability, foaming capacity, foaming stability and gelation of the two proteins were tested and compared. The results showed that oil absorption, emulsion capacity and gelation of protein from fired tea was better than that extracted from fresh tea, but the solubility, water absorption, emulsion stability, foaming capacity and foaming stability of protein from fresh tea was better than that extracted from fired tea. The molecular weights and amino acids composition of the two proteins were also studied. The results showed that the molecular weights of the two proteins have little difference, the amino acids composition from fired tea was better than that extracted from fresh tea but CYS.

Keywords：Tea protein; Alkaline method; Functional properties ; Amino acid; Two-dimensional electrophoresis