本文采用一芽三四叶的鲜叶原料，比较了信阳绿茶、3个不同做青程度的信阳茶和信阳红茶的品质及其抗氧化活性，此为江北茶区小叶种茶树品种的鲜叶进一步开发利用提供理论依据。通过分光光度计、液相色谱和气相色谱-质谱联用仪检测5种茶主要生化成分和挥发性成分，利用1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)法检测此5种茶的抗氧化活性，最后进行感官审评。结果发现：不同做青程度的信阳茶中所含主要成分的含量及组成存在差异，随着做青程度加深，茶多酚由21.17%降到18.90%（P＜0.05），氨基酸由3.43%增加到3.73%（P＜0.05），黄酮由5.63mg/g增加到6.55mg/g（P＜0.05），香气成分呈递增的趋势，尤其单帖类物质增加明显，如β-蒎烯由0.13ug/g增加到0.37ug/g、E-β-罗勒烯0.05ug/g增加到0.15ug/g（P＜0.05）。感官审评发现，轻度做青处理所制的茶叶品质相对较优。通过计算不同做青处理所制茶叶清除DPPH自由基半抑制浓度IC50值（Half maximal Inhibitory Concentration, IC50），发现随着做青程度加深，IC50值在增大，1/IC50值与茶多酚呈极显著正相关（P<0.01），与氨基酸和黄酮呈极显著负相关（P<0.01），与19种挥发性成分呈显著负相关（P<0.05），说明适当的做青工艺可以改善一芽三四叶所制信阳绿茶的品质。

This paper explored the quality and antioxidant activity of Xinyang green teas, Xinyang black tea ,and Xinyang tea with different degrees of tossing, these teas were made from the fresh tea sticks with one bud and three leaves or four leaves, which provided a theoretical basis for the further development and utilization of the fresh leaves of small-leaf tea varieties in the northern tea region. The main biochemical and volatile components of the five teas were detected by spectrophotometer, liquid chromatography and GC-MS. and then the antioxidant activity was detected by DPPH method, and finally sensory review was conducted. Results: There were differences in the content and composition of the main components contained in the Xinyang teas with different degree tossing. As the tossing degree deepened, the tea polyphenol contents decreased from 21.17% to 18.90%, and the difference was significant (P<0.05). While amino acids increased from 3.43% to 3.73%, and the difference was significant (P<0.05), and flavonoids increased from 5.63 mg/g to 6.55 mg/g too, and the difference was significant (P<0.05).The aroma components showed a trend of increasing, especially the increase of monoterpenes, such as β-Pinene increased from 0.13ug/g to 0.37ug/g, E-β-Basilene increased from 0.05 ug/g to 0.15ug/g, and the difference was significant (P<0.05).In the sensory review, the quality of tea by lightly tossed was better than Xinyang green tea and other degree tossing teas. By calculating the IC50 values of the scavenging strength of DPPH radicals of the teas different degrees of tossing, it was concluded tha tthe degree of tossing was deepening, and the IC50 value was increasing; Correlation analysis, 1/IC50 value was very significant positively correlated with tea polyphenols (P<0.01), and 1/IC50 value was very significant negatively correlated with amino acids and flavonoids (P<0.01). and significant negatively correlated with 19 volatile components (P<0.05). As a result, the quality of coarse Xinyang green tea could be improved by proper tossing process.

2021年河南农业大学《茶叶生物化学》课程思政理念融入教学全过程与实践项目(2021XJGX101)；2021年横向课题豫新茶研制与开发项目(30801981)；2022年服务河南省信阳市茶企科技特派员项目（30802540）。