Types and efficacy of oolong tea Narcissus tea in northern Fujian is one of the two major varieties of oolong tea in northern Fujian with unique quality. Is daffodil tea delicious and strong? (Jian 'ou County Records 1929),? Is the fruit a crown of tea? .
Guangdong oolong tea
Among the types of oolong tea, only the processing method of Guangdong oolong tea originated from Wuyishan, Fujian, so its style and genre are somewhat similar to Wuyi rock tea, and its shape is strip.
Oolong tea in Taiwan Province Province
Taiwan Province oolong tea is one of the most fermented oolong teas, and it is also a recent black tea. Stripes are curly, copper-brown, tea soup is orange-red, with pure taste and rich fruit aroma. After brewing, the leaves are red at the bottom and green at the belly. Among them, the frozen top oolong tea in Nantou County (commonly known as frozen top tea) is very famous and the most precious.
South Fujian Wulong tea
Anxi Tieguanyin: named after its weight as iron and beauty as Guanyin, it is the best oolong tea in Fujian. Produced in Anxi, southern Fujian. ? Tieguanyin? It is not only the name of tea, but also the name of tea varieties. This kind of tea is compact in shape, some like scales and some like dragonfly heads. Because caffeine evaporates with water, a layer of frost is formed on the surface, which is called. Sand green frosting? . This tea tastes strange when it is brewed. Sipping in hot water, the aroma is overflowing, and the bottom of the throat is sweet, which is called seven bubbles and more fragrant.
Phoenix Narcissus: The main producing area is Fenghuang Township, which is generally a combination of narcissus varieties and place names. Phoenix narcissus? .
The efficacy of oolong tea is 1, skin care and anti-aging. After drinking oolong tea, it does not simply reduce the sebum content, but has a greater effect on people with high sebum content than those with low sebum content, indicating that oolong tea has the function of regulating the balance of sebum content. The anti-aging experiment conducted by Fujian Institute of Traditional Chinese Medicine showed that the lipid peroxidation in the liver of two groups of animals fed with oolong tea and vitamin E respectively decreased significantly, indicating that oolong tea has the same anti-aging effect as vitamin E.
2, can improve skin allergies According to data, drinking 1 liter oolong tea every day can improve skin allergies. It is said that most patients with dermatoses suffer from allergic dermatitis. So far, the cause of this dermatitis is not clear, but oolong tea can inhibit the development of the disease.
3, to prevent the occurrence of tartar, prevent tooth decay, a cup of tea after meals in addition to quenching thirst, refreshing, oolong tea also has the role of preventing tooth decay. The cause of tooth decay is that bacteria invade the tooth tissue and produce enzymes that cause tooth decay in the tissue. This enzyme works with sugar contained in food, leading to tooth decay. This kind of tooth decay substance and bacteria adhere to the teeth to form tartar, and after accumulation, tooth decay occurs. Polyphenols contained in oolong tea can inhibit the production of tartar enzymes, so drinking a cup of oolong tea after meals can prevent the occurrence of tartar and tooth decay.
4. Improve energy metabolism. In Japan, water, green tea and oolong tea were tested to improve the basic metabolic function. The results show that water has no special effect. Green tea can improve the metabolism of 4 calories 1 hour, and oolong tea can improve the metabolism of 9 calories the most!
Problems existing in the current prevention and control of tea plant diseases and insect pests According to the requirements of the prevention and control of tea plant diseases and insect pests under the current new situation, there are the following problems:
1 Some main tea plant diseases and insect pests still lack new effective control techniques. Although the main tea pests and diseases have been effectively controlled, the pest population can basically be controlled. However, on the eve of China's entry into WTO, many developed countries formulated new MRL standards for pesticides in tea, which restricted some technologies that have been used for many years. For example, at present, the most important pest species in tea production, Empoasca vitis, has long adopted chemical control technology, and the effect of long-term use of dimethoate in many areas has been declining, and the MRL of it has gradually become stricter abroad. Fenvalerate is an important pesticide used to control Empoasca vitis in tea gardens since 1980s, and it has been banned from tea production by the Ministry of Agriculture since June 1999 1 1. With the popularity of famous and excellent tea, the picking standards are becoming more and more tender, so that more tender shoots and stems are left on the trees. Compared with the old picking standard, which can collect a large number of cicada eggs, this actually weakens the agricultural control of the false-eyed green leafhopper. Bemisia tabaci is the main pest in many tea gardens since 1990s. As the MRL of buprofezin (Youle and Pusuling), which has been widely used for a long time, is set at 0.02mg/kg in the new EU standard, this pesticide which is very effective in controlling Bemisia tabaci can only be stopped in tea gardens, and no pesticide can be completely replaced at present. Tea black moth only happened locally and sporadically before the 1980 s, and it was not harmful as a whole. However, since the end of 1990s, its occurrence area has been increasing, and there is still a lack of effective control measures.
In addition to tea pests, chemical control methods are also used to control tea bud and leaf diseases. Because MRL has strict standards for common fungicides, it is necessary to put forward comprehensive control measures for tea bud and leaf diseases in order to reduce the use of chemical pesticides as soon as possible.
The excessive rate of pesticide MRL in tea is high, which affects the export of tea. In 1960s and 1970s, the residue of DDT and BHC in China tea was a serious problem affecting tea export. With the attention of governments at all levels, the safe and rational use of pesticides and integrated pest management technology has been implemented. Therefore, since the mid-1980s, the problem of pesticide residues in tea has been fundamentally solved. More than 98% of tea exported from China and more than 95% of tea sold in China meet the international and domestic allowable standards. However, on the eve of China's entry into WTO, some developed countries, especially EU countries, have successively expanded the MRL detection range of pesticides in tea, from only 6 pesticides in the past to nearly 100 pesticides, and at the same time greatly reduced the MRL value. For example, the MRL of fenvalerate in tea was 10 mg/kg before July 2000, but it was changed to 0. 1 mg/ kg after July 2000, and the minimum detection standard for many pesticides was 0.02mg/kg. Therefore, in 2000, the rate of pesticide residues in tea exceeded the standard was very high. It must be noted that this over-standard rate is calculated according to the new standards of the European Union. If calculated according to the standards promulgated by our country, most tea leaves still meet the standards. According to the test results, fenvalerate, fenpropathrin and Youle are the highest over-standard rates. With the attention of governments at all levels, this phenomenon of exceeding the standard is obviously improving.
Lack of technology and pesticides suitable for pollution-free production