Hot And Humid Post-processing Technology Research And Effect Evaluation In The Improvement Of Black Tea Flavor

Black tea is the mainstream of the international tea market products for the world’s largest tea. With the revealed that black tea health care function of black tea is more and more important position in the international market, China as a major black tea producing countries and king pin, its production and sales are increasing, but widespread poor flavor, quality problems such as instability, disperse production and smaller. How to improve the flavor, stable quality, implement product standardization and processing scale, to promote the development of Chinese black tea is of great significance. This topic in view of the finished product is common black tea aroma owe taste pure, raw ills such as flavor, the flavor, tea, tea, tea review and test, biochemistry subject theory as a guide, to the finished product tea as raw material, hot and humid post-processing methods, to improve the possibility of black tea flavor and process scheme was studied, and its flavor improvement effect is evaluated. The main research results are as follows:(1) by setting the damp and hot single factor (time, temperature, water content) of different processing parameters, the aroma, taste and tang three flavors factor scores, respectively, to the value of the optimum parameters. The results showed that hot and humid post-processing of black tea has a great influence on color, aroma, taste, the best parameters for time 5 h, temperature 65 ℃, water content of 10%.(2) according to the results of single factor experiment, the design temperature, time, water three factors and three levels orthogonal experiment, flavor scores for evaluation standard, the selected optimum technological parameters combination of hot and humid post-processing. The results showed that 9 of damp heat treatment combinations of tea samples review score between 77.4～89.1, extremely significant difference (F= 10.868* *> F0.01 (8,9)= 5.47, P< 0.01). Optimal combination of wet and heat treatment temperature of 65 ℃, water content of 10%,7 h.(3) through the post-processing of the optimal process conditions of the sensory quality of black tea with the time changing law is studied. Results show that the temperature of 65 ℃, water content under the condition of 10%, black tea with the increase of damp and hot processing time, aroma of grass gas gradually into a sweet smell, looked from the bright red orange, gradually deepening to red, taste the bitter, green turn into comfortable, mellow to 7 h after black tea flavor quality has reached the optimal.(4) to the hot and humid post-processing of the optimal process conditions of the main flavor components of black tea with the time changing law is studied. No significant difference results show that the average content of water extract, tea polyphenol content is reduced to 11% from 14%, difference is very significant. Soluble sugar content decreased to 3.39% from 4.25%, difference is very significant. The change of the amino acid content in lower first, then gradually increase trend, content is significant difference. Tea pigments are extremely significant difference, theafiavins content reduced to 0.41% from 0.42%, tea red pigment content & increase by 5.17 to 5.83%, tea brown content increased from 4.,72% to 7.05%.(5) of black tea samples respectively before and after the wet and heat treatment quality, the main flavor components and amino acid composition, catechins composition, contrast analysis of aroma components.From the comparison between results of quality analysis shows that black tea reprocessing the damp and hot, appearance, and there was no difference in the raw materials of tea leaves, and grass aroma on gas disappear, sweet sweet show, tang sehong bright, the taste of bitter, green taste mellow into fresh.From the main flavor components content of contrast analysis indicate that no significant difference between water extract content, sample processing was reduced by 3.64% compared with the same tea polyphenols. amino acids increased by 0.08%, soluble sugar was reduced by 0.86%, theafiavins was reduced by 0.01%, tea red pigment increased 0.66%, tea brown pigment increased by 2.33%.From comparison and analysis results show that the section of the amino acid composition in addition to the significant difference to aspartic acid, the rest were not significant difference between the components. From catechins composition analysis results show that the handle sample is the same volume decreased significantly, the ester type catechins has no obvious change, total ester type catechins decreased, especially the EGCG and ECG decreased significantly. From the aroma components of comparison and analysis results show that both give priority to with alcohols, aldehydes, esters, sample processing compared with raw materials of tea down 1.03% salicylic acid methyl ester, hexanol, anti-2-hexylene glycol as the fragrance of grass gas matter content were also decreased, and the sweet smell of aroma components increase.To sum up, time, temperature of 65℃,7 h moisture content 10% of the hot and humid post-processing technology can better improve the tea flavor.