Studies On The Yellowing With Piling Process And Choosing Suitable Varieties For Making Yellow Tea

Yellow tea is one of the six tea in China, the world the only independent production. The basic process:Fixing-boring yellow-rolled-dry, the key process of boring yellow, and therefore has a unique "yellow" quality:dry tea golden,liquor color bright yellow, the bottom yellow. Yellow tea addition to the unique shape of the beauty of their nutritional and pharmacological composition among the six major tea three tea.experts recommended as the most suitable for drinking tea.In order to proven quality changes in the process of yellow tea, referring to the processing technique of Weishanmaojian,during the process of yellowing with piling, tea leaves were sampled out at the point of six phases(1h,2h,3h,4h,5h,6h, respectively). They were assessed by the combination of approach of sensory evaluation and physical and chemical analysis. The results showed that:with the prolongation of the duration of yellowing with piling, the color of tea leaves changed from green to yellow gradually.In particularly, after5h of yellowing with piling, the color of tea soup changed from olivine to light yellow with brightness, moreover, the taste became delightfully fresh and mellow; during the whole process, the content of amino acid increased, while the counterpart of Polyphenols decreased with the least ratio of Phenol and ammo acid at5h of yellowing with piling; soluble protein decreased slowly, and simultaneously, the content of soluble sugar rose a little bit.However, there is a comparatively large loss of Chlorophyll-a, Chlorophyll-b and total chlorophyll for the reason of degradation at the phase of Inactivation and Yellowing. Besides, small quantities of TF were also produced. In a word,a duration of5-6hours seems to be suitable for yellow tea.Optimum filter out the yellow tea processing parameters in order to optimize the conditions of boring yellow, the subject of the boring yellow3factors and3levels of orthogonal experimental design, experimental results show that:from the sensory evaluation analysis, when the tea water content60%percent of the boring yellow temperature to40℃, the boring yellow time was6h, tea-like stem tea color and endoplasmic aroma taste from the containing composition analysis, most of the tea samples containing ingredients to retain most of the mostboring yellow conditions good:60%water content, boring yellow temperature of40℃nausea yellow time6h. The results of sensory evaluation consistent with the physical and chemical analysis results, which may have yellow tea boring yellow optimal process parameters:water content60%, nausea yellow temperature of40℃, nausea yellow time6h.Less suitable for making varieties for yellow tea at home and abroad screening, in order to promote the healthy and rapid development of the yellow tea industry, subject to the Hunan existing tea varieties as raw materials, investigation and appropriate system of the traits of different tea varieties, compared to springbefore and after the summer, and autumn yellow tea into tea contains ingredients, and into the tea expert password reviewers. Tea for different seasons, pointing out that the place should be noted that in the processing methods. The results showed that:sharp wave Huang Hsiang Fei Tsui Fuding cents and Pekoe early as suitable for making yellow tea quality is better, especially the sharp wave yellow. Processing yellow tea fresh leaves in the spring, the quality was significantly better than the summer and fall, the fall of fresh leaves can not be processed into high-quality yellow tea.