杀青方式对机采绿茶理化品质的影响

为了提高茶树机采绿茶杀青品质,以机采鲜叶为原料,比较微波、汽热、电热滚筒和电磁滚筒耦合热风4种杀青方式所制机采绿茶的感官品质、茶叶内含成分、色泽和香气。结果显示：电磁滚筒耦合热风杀青所制绿茶的感官得分（89分）最高,所制干茶的色相值（a/b）相对更绿（p<0.01）,酚氨比较低（p<0.05）,非酯型儿茶素、酯型儿茶素和儿茶素总量也相对较低（p<0.01）;电磁滚筒杀青所制绿茶的栗香型成分含量较高,如藏红花醛、癸醛、β-环柠檬醛、庚醛和3,7-二甲基-2,6-二辛烯醛等高级醛类,香叶基丙酮、β-紫罗酮和1-戊烯-3-酮,反式-2-辛烯醇、芳樟醇、反式-橙花叔醇等,以及二甲硫、2-甲基呋喃和1-乙基吡咯等杂环化合物,说明电磁滚筒耦合热风杀青集成了不同工艺特点,所制机采绿茶滋味鲜爽,栗香明显,该工艺有利于提高机采绿茶品质,对实际生产具有指导作用。

The Effects of Different Fixation Methods on the Quality of Green Tea Harvested by Machines

The effects of different fixation methods (including microwave, steam-hot air, electric heating roller and and electromagnetic heating roller-hot air fixation methods) on the sensory quality, tea color, main taste and the aroma components of green tea harvested by machines were studied. The electromagnetic heating roller-hot air fixation treatment significantly improved the sensory quality of the green tea. The hue of color (a/b) of the dry tea was obviously improved (p<0.01). The ratio of polyphenols to amino acids was the lowest (p<0.05). The content of simple catechines and complicated catechines decreased (p<0.01). Total catechines, the content of baked and roasted aroma components including safranal, decanal, β-cyclocitronillon, heptaldehyde, 3,7-dimethyl octenal, geranylacetone, β-ionone, 1-penten-2-one, (E)-oct-2-en-1-ol, linalool, trans-nerolidol, methyl pyruvate sulfide, 2-methylfuran, 1-ethylpyrrole were the highest. The electromagnetic heating roller-hot air fixation had the combined advantages of different fixation methods, and could produce green tea with refreshing chestnut aroma taste, which could be used for green tea production harvested by machines.