The Study On Key Process Parameters Of Tatry Buckwheat Leaves Tea Process And Its Aroma Components

Tea and tartary buckwheat all have healthcare function. The tartary buckwheat leaf tea that made by refer to the method of oolong tea, not only adds a new breed of tea, but can also bring some economic benefits. The processing steps of tatary buckwheat leaf tea: picking; cleaning; Airing; sunning; airing the leaves; shaking and parking; kill out; three times knead three times bake; Spreading. The main results of this experiment are as follows:1. In order to determine the shaking way, to choose the tea samples and tea soup’s bioflavonoid content as an index to compare the influence that hand-made shaking and mechanical shaking for it. The experiment result was: hand-made shaking tea samples, tea soup’s bioflavonoid contents were 5.00%,0.039mg/mL; mechanical shaking tea samples, tea soup’s bioflavonoid content were 7.20%,0.036mg/mL. Mechanical shaking was better ultimately.2. After the single-factor experiment of the key technology, applied the Plackett-Burman to screen the factors, the results were kill out temperature, shaking and parking temperature, kill out time were notable and P<0.05. Fuzzy mathematics analysis and Response surface analysis were applied to get optimum process parameters:shaking and parking temperature 36.91 ℃ , kill out temperature 176.3 ℃ , kill out time 86.3s.3. Single factor experiment and Orthogonal experiment design were applied to get optimum brewing methods, the results were: brewing time 11min, not less than 9min preferably; brewing temperature 100 ℃ ;brewing tea and water proportion 1:75 (g /mL),under a brewing time. Brewing time were more than 5 times preferably, when brewing time more than one.4. Solid-phase micro-extraction technology and GC-MS were applied to extract and analyze 4 tea samples (dry tatary buckwheat leaves tea; tatary buckwheat leaves tea soup; Longjing tea; Tieguanyin tea) aroma components. The results were: dry tatary buckwheat leaves tea aroma components is slightly different from the tatary buckwheat leaves tea soup due to the chemical reaction after boiling brewing. Tatary buckwheat leaves tea soup compared with Longjing tea soup and Tieguanyin tea soup, not only has the similar composition, but also has its the special aroma substance .For example, nonanal, (E)-2-Hexenal, and so on.5. Analyzed the dry tatary buckwheat leaves tea nutrient content, the polyphenol content was 7.48g/100g, caffeine content 2.12 g/100g, bioflavonoid content 9.69 g/100g. Compared the tatary buckwheat leaves tea soup, Longjing tea soup, Tieguanyin tea soup antioxidant capacity, the conclusion was: DPPH·scavenging ability and super oxygen anion removal ability of the tatary buckwheat leaves tea was higher than the rest of tea,respectively:90.5%、 66.7%. Longjing tea has strong hydroxyl radical scavenging ability 51.8, Tieguanyin tea has strong total reducing capacity, the absorbance was 0.546. In summary, tatary buckwheat leaves tea has strong antioxidant capacity.