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摘要：本实验系统研究了原料茶不同干燥工艺对茶饮料稳定性的影响，传统茶叶干燥方式中主要有炒干跟烘干，炒干主要依靠茶叶物料与加热的固体表面的直接接触而获得能量，达到干燥的目的；烘干是依靠热空气与茶叶物料的流动接触而使茶叶达到干燥的目的；滚筒辉干是滚筒在不断翻滚过程中对茶叶进行加热从而达到干燥的目的。通过分析原料茶不同干燥工艺对所制茶饮料浊度、色差的影响，结合感官审评结果，确定原料茶的最佳干燥工艺。并通过分析茶多酚、氨基酸、黄酮等主要生化成分的变化规律，探索茶饮料汤色稳定性与主要生化成分之间的关系。主要研究结果如下：52871
茶多酚的含量变化呈现出先上升后下降最后趋于平稳的趋势，3种不同干燥方式中，以烘干干燥方式处理茶叶茶多酚的稳定性最好。在55℃条件下，滚筒辉干干燥方式表现较为稳定。氨基酸的含量变化呈现先上升后下降的趋势， 在3种干燥方式中，炒干干燥处理氨基酸含量的变化最为稳定。3种干燥方式，黄酮百分含量变化各有不同，炒干干燥的黄酮最为稳定，尤其是在4℃贮藏条件下，黄酮随着贮藏时间的延长趋于稳定。
在较低温度条件下，明度（L值）变化不是很明显，但是随着时间的延长，明度（L值）变化较大。通过分析抗高温色变能力和抗浑浊能力，得出烘干最佳，炒干次之，滚筒辉干最差。长期储藏滚筒辉干较稳定，亮度好。感官审评结果表明，炒干方式对茶汤的滋和香气的稳定性最好，烘干次之，滚筒辉干最差；在55℃储藏条件下，滚筒辉干的变异系数比烘干小，且与炒干比较相差不大，表明在较高温度下滚筒辉干的滋和香气稳定性较好。
毕业论文关键词：茶饮料；稳定性；贮藏；变异系数
Abstract
This paper systematically investigated the influence of different drying methods of tea raw materials on the stability of the tea beverage. Traditionally, there are two tea drying methods, frying and baking frying methods, the leaves were dried by the energy from heating surface while in baking method hot air was used. Drumming frying is a new method to traditional method which is the roller in the process of continuous rolling to heat the tea to achieve the purpose of drying. In addition, the relationships within the dry methods and contents such as polyphenols and amino acids and stability of tea beverage were also discussed. The major results are as follows:
Changes in the contents of polyphenols showed increased and then declined, finally stabilized trend, In three different drying methods, baking frying method for processing polyphenols best stability. At 55 ℃ condition, drumming frying has a more stable performance. In the three kinds of drying modes, frying method approaching to raw materials changes more stable for content of polyphenols 。In the three kinds of drying methods, the changes in percentage of flavonoids have different manifestations, frying method made flavonoids most stable, especially at 4 ℃ storage conditions, with the extension of storage time the content of flavonoids are more stable.
At lower temperatures, Lightness (L value) did not changed significantly, As time goes by, the lightness (L value) changed greatly. Through analyzing the anti-discoloration and comparative anti-turbidity capabilities, the result showed that baking frying methods on the stability of tea liquor color, then was frying, last was drumming frying. drumming frying with long-term storage showed more stable, and high brightness. Sensory evaluation results showed that the stability of the frying method made flavor and aroma of the best, followed by baking frying, last by drumming frying . At 55 ℃ storage conditions, the drumming frying for coefficient of variation is smaller than baking frying and similar with frying. Showed that drumming frying had a good stability in flavor and aroma.