摘要：绿茶饮料是以绿茶的水提取液或浓缩液、速溶茶粉等为主要原料，经过滤、调配、罐装、灭菌等工序加工而成，含有一定量的茶叶有效成分的液体制品。由于纯茶饮料茶的成分含量高，茶汤浓度较大，茶汤中主要成分容易氧化、络合，造成茶汤色泽褐变，浑浊沉淀，影响其感官品质，进而影响到绿茶饮料的市场价值。本课题研究探讨pH值、食品添加剂包括氯化锌、抗坏血酸,亚硫酸钠，硫酸氢钠等及其组合，对绿茶饮料的护色效果。研究结果显示，当绿茶饮料pH为5.0时色泽的稳定性最高，氯化锌、抗坏血酸对保持绿茶茶汤色泽的稳定效果最好。调节茶汤的pH值至5．O，再加入0．03％的氯化锌、0．02％的抗坏血酸、绿茶饮料的护色作用最好。5903
关键词：绿茶饮料，pH值，护色，添加剂
Development of Color Protecting Technology of Green Tea Beverages
Abstract: Green tea beverage is made with green tea ’s water extract or concentrated tea liquid, instant tea powder as the main raw materials, though filtration, blending, filling, sterilization and other processes, which contains certain amount of active ingredients. Because of the higher content of tea ingredients in pure tea drinks and the larger concentration, the main component of tea can easily be oxidized, induced complexation, resulting in browning color of tea beverage, muddy sediment, affecting quality of tea beverage, limiting the further development of pure tea drinks. The thesis focuses pH value, food additives including mainly ZnCl2, Vc, Na2SO¬3 ,NaHSO4 and their combinations on the color protection of green tea beverages. The results indicated that the stability of green tea beverage was the highest when pH value was 5.0. In addition, ZnCl2 and Vc the best for the color protection. The optimal conditions for protection the color of green tea beverage were: adding 0.03% of zinc chloride and 0.02% ascorbic acid and under the pH 5.0.
Key Words: Green tea beverage, pH value, Color protection, Additive
目 录
1 引言 1
1.1绿茶饮料概述 1
1.1.1 绿茶及绿茶饮料的功能 1
1.1.2 茶饮料的分类 2
1.1.3 茶饮料生产工艺 2
1.1.4 绿茶饮料的现状 3
1.2 绿茶饮料护色 3
1.2.1 绿茶饮料褐变机理 4
1.2.2 绿茶饮料护色技术 4
1.3 本课题的立题背景、研究内容及意义 6
2 材料与方法 7
2.1 实验材料 7
2.2 实验仪器与设备 7
2.3 实验方法 8
2.3.1 绿茶变色研究 8
2.3.2 添加外源物质对绿茶饮料色泽稳定性的影响 8
2.3.3 pH值对绿茶饮料色泽稳定性的影响 8
2.3.4 不同方式组合对绿茶护色的影响 9
3 结果与讨论 10
3.1绿茶饮料变色研究 10
3.1.1实验结果与分析 10
3.2添加外源物质对绿茶饮料色泽的影响 11
3.2.1 四种外源物质的最适添加量结果分析 11
3.2.2 不同外源物质对绿茶吸光度影响结果分析 12
3.3 pH值对绿茶饮料色泽的影响 14
3.3.1 不同pH值下绿茶饮料吸光度结果分析 14
3.3.2 不同pH值下绿茶饮料感官评定结果分析 15
3.4添加剂复合使用对绿茶饮料护色的影响 16
4结论 18
致 谢 20
参考文献 21
1 引言
1.1绿茶饮料概述 绿茶饮料护色技术研究+文献综述:http://www.751com.cn/shiping/lunwen_3176.html