About Ziyang Selenium-rich Tea

Ziyang County has produced tribute tea since the Tang Dynasty, and there are many written records in the historical records of the Tang, Song, Ming, and Qing Dynasties. Due to frequent wars and traffic jams, tea from the south could not be transported to the northwest at the end of the Qing Dynasty and the beginning of the Republic of China. However, Ziyang tea benefited from its favorable geographical location and convenient water transportation by the Han River. Not only did it not stagnate due to the war, but its sales expanded, "approximately more than 300,000 jins are produced every year.". In the 33rd year of the Republic of China (1944), the sales volume of Ziyang tea reached 260 tons. Ziyang has tea that is good for drinking and water for tea. The water of the Han River and Ren River is clear and pollution-free, providing necessary conditions for tea production and drinking.

Ziyang tea developed rapidly after the founding of the People's Republic of China. In March 1953, Ankang District established a tea guidance center with Ziyang as the focus and set up the largest tea test station in northwest China in Wafangdian, with Hongchunba, Maobaguan, Wafangdian, and Huangutan as key tea areas. Cultivation, the county's tea garden area reached 1,700 hectares.

In early 1965, a tea production boom emerged in the county. County-level agencies and district community cadres went deep into the tea areas to organize farmers to carry out short-tassel cuttings and seedling cultivation of tea trees. The purchasing department purchased tea seeds in large quantities and developed several new tea gardens. This was later interrupted due to the "Cultural Revolution." Historically, Ziyang tea cultivation was scattered. Except for the Wafangdian Tea Experimental Station, there were no rows of tea trees or patches of tea gardens in the county. Tea trees grew in crop fields and on hillsides. Tea farmers were not used to top-dressing tea trees. They don’t know how to prune and renovate, and the government doesn’t allow and is reluctant to occupy good fields and suitable land to grow tea.

In 1980, the exceptional quality of Ziyang tea was officially recognized. It was discovered that Ziyang rocks, soil, and water are rich in selenium, and tea has the best content. This finding was widely acknowledged by tea experts and scholars across the country. In June 1986, researcher Chen Qikun, president of the China Tea Society and a famous tea expert, named Ziyang tea 'Ziyang selenium-rich tea' when he inspected tea production in Ziyang. Since then, selenium-rich tea has become Ziyang’s patent, and its brand effect has become prominent in the national tea market. In 1999, the county began to return farmland to forest, and most of the land was planted with economic forests, mainly tea.

In 2001, a significant milestone was reached in Ziyang tea production. The county government decided to vigorously develop local tea tree varieties in Ziyang and use good fields and land in Huangu, Maoba, Xiangyang, and other places to build tea farms with local tea varieties. This marked a shift from the traditional production model to a more modern and efficient approach. In October 2004, the state officially announced that Ziyang tea was the origin of selenium-rich tea and that national intellectual property rights protected it. In 2007, several high-quality and high-yielding tea gardens concentrated in low mountains and rivers were developed by constructing modern gardens, ecological projects, demonstration projects, and densely planted tea gardens with improved clones. In 2010, the county's total tea garden area was 11,500 hectares, with a total tea output of 2,983 tons, including 1,680 tons of famous tea, and a tea output value of 360 million yuan.

The highest peak in Ziyang County is 2,522 meters above sea level, and the lowest altitude is 280 meters. It has the climate characteristics of "three-dimensional agriculture." The formation of a unique regional microclimate with a synergy of water and heat, lots of diffuse light, and a significant temperature difference between day and night are conducive to the growth and development of tea content, especially the synthesis and accumulation of soluble substances, making tea rich in content, rich in aroma, and strong in flavor. Bubble. Most areas within the territory are suitable for tea tree cultivation and are green, organic, safe, and sustainable tea production areas, complying with NY5020-2001 "Pollution-free Food, Environmental Conditions of Tea Origin" and NY/T5018-2001 "Pollution-free Food" "Tea Production Technical Regulations" and Shaanxi Province DB61/T307-2003 "Natural Selenium-Rich Tea Standard Complex" stipulates and requires the environmental conditions of the production area for the development of natural selenium-rich tea.

Ziyang has dual natural barriers, the Qinling Mountains and Phoenix Mountains in the north, to block the Siberian cold current and dry and cold air intrusion. It is protected by the natural ecological forest of Daba Mountain in the south. The Han River and Ren River in the southeast can fully absorb the southeastern warm and moist air currents, forming warm and humid water all year round. The climate features hot weather and four distinct seasons. Various climate factors in Ziyang County are consistent with the annual precipitation of tea trees growing more than 900 mm, the monthly rainfall during the production season more than 100 mm, the yearly effective accumulated temperature more than 4500°C, the annual average temperature higher than 14.5°C, the sunshine percentage less than 45%, and the frost-free period more than 260 days. Requirements. Ziyang's forest coverage rate is 55.7%, there are few industrial enterprises, no industrial pollution in the atmosphere and water areas, and the tea garden's ambient air quality is excellent. Tested by the Northwest Environmental Monitoring Station of the Ministry of Agriculture, the daily average concentrations of total suspended particulate matter, sulfur dioxide, nitrogen dioxide, and fluoride (F) per cubic meter in the air are less than 0.3, 0.15, 0.1 mg, and 7Ug respectively. Natural precipitation and river water quality are good and pollution-free. The salinity of various water sources in the county is between 69-430, and the pH value is between 6.4-8.3. It is weakly alkaline and weakly acidic water, all meeting the national Class II standard.

The county's soil shows significant mountainous vertical zonal succession changes. Below an altitude of 1,400 meters, the base zone is yellow-brown soil distributed in most areas in the north, central, and southwest. Among them, yellow-brown soil is dominant below an altitude of 900 meters. Brown soil is mainly distributed in areas above 1,400 meters in Daba Mountain in the south. Flavor-aquic paddy soil is distributed primarily in river valleys and terraces below 1,000 meters above sea level. Except for the alkaline soil distribution in the Panxiang River, Qingshiban River, and Donghe River basins in the territory, the soil-forming parent rocks in other places are acidic, with a pH value between 4.5 and 6.8. The organic matter is 1.68%, which is a medium level. The nitrogen content is 0.144%, which is an upper-middle level. It is rich in available potassium, greater than 70 mg/kg. The soil is suitable for the growth of tea trees, and the soil ideal for tea is broad. Selenium-rich rock formations that are rare in China are widely distributed, such as siliceous, carbonaceous schist, marl, mica schist, etc., from the Early Paleozoic. The average soil selenium content reaches 0.49 mg/cubic meter, with the highest value reaching 3.98 mg/cubic meter. During planting, The standard range of selenium content in the natural selenium-rich tea soil in the area is 0.5-6.9 mg/kg. The content of heavy metal elements such as cadmium, mercury, arsenic, lead, chromium, and copper and toxic and harmful substances such as cyanide, chloride, fluoride, and petroleum in the soil is shallow, and some are even undetectable. After an on-site inspection by the Northwest Environmental Inspection Station of the Ministry of Agriculture in Ziyang, all indicators of the tea garden's environmental conditions can meet the requirements for pollution-free food production. After samples were sent to the Tea Research Institute of the Chinese Academy of Agricultural Sciences for testing, the results showed that Ziyang's selenium-enriched tea complies with pollution-free food safety requirements and has the conditions to develop green food and organic tea.

The Ziyang species is a local population species formed through long-term natural evolution and artificial selection in a unique natural environment. It has early germination, dense branches, strong stress resistance, high yield, rich content in fresh leaves, and coordinated proportions. It is especially suitable for making high-quality green tea. In 1965, it was recognized by the Ministry of Agriculture as one of the country's 21 local tea tree varieties. Under the same fertilization and management conditions, Ziyang varieties' quality components (amino acids) are higher than those of foreign varieties. Still, the ratio of polyphenols to amino acids is relatively lower than that of foreign varieties. Ruan Yucheng, a late researcher and doctoral supervisor at the Tea Research Institute of the Chinese Academy of Agricultural Sciences, believes that the Ziyang species is one of the seven varieties in the country with a unique ripe chestnut aroma.

On September 6, 1989, Ziyang selenium-rich tea passed the authoritative appraisal in Beijing, and its quality was fully affirmed by all appraisal experts: "Ziyang selenium-rich tea is a health product with broad prospects, especially beneficial to human body's selenium supplement, and It has certain anti-cancer, anti-cancer, and anti-aging effects. It is the first selenium-rich tea approved in China. Its research results are at the leading level in the country. This research has significant economic and social benefits. It is the first domestic selenium-rich tea development research. It sets a precedent.”

Ziyang is a remote agricultural county in a mountainous area. Large enterprises cause no industrial pollution, and the ecological environment is good. In agricultural production, except for a certain amount of chemical fertilizers and pesticides used in grain production, only a tiny amount of chemical fertilizers or no pesticides are used in other economic crop production. According to the inspection by the Northwest Environmental Inspection Station of the Ministry of Agriculture, all indicators of the environmental conditions of the tea gardens in the territory can meet the requirements for the production of pollution-free food, which can be said to be safe and hygienic.

Although Ziyang is located at the northern edge of my country's tea area, its unique geographical location and topographic structure form a subtropical, humid monsoon climate. The tea trees have a long growing season; water and heat are in the same season, which is well matched. The mountains are shrouded in clouds and mist, cloudy, high humidity, and low sunshine. The climate characteristics of the significant temperature difference between day and night are particularly suitable for the growth of tea trees. They are more conducive to the synthesis and accumulation of tea content. The content is rich and in various proportions, especially the taste substances that play an essential role in the aroma and taste of tea. , such as amino acids, free catechins, caffeine, and other substances with higher content. Ziyang selenium-rich tea has been famous throughout the country for its high aroma, spicy taste, sweet aftertaste, and resistance to brewing. It has become a representative of the northwest tea area and is a natural product.

Scientific research has confirmed that only Enshi, Hubei and Ziyang, Shaanxi are selenium-rich in my country's tea areas. Selenium-rich rock formations, which are rare in my country, are widely distributed in Ziyang County. The soil developed from the rock formations contains selenium as high as 3.98 mg/ Kilogram, the material basis of Ziyang tea’s natural selenium content. After measurement and analysis, the selenium content of Ziyang tea is more than 0.3 mg/kg, which meets the requirements of Shaanxi Province local standard DB61/T307 "Natural Selenium-rich Tea Standard Complex."

For spring tea picking in Ziyang County, under normal weather conditions, the shallow mountains along the Han River usually open seven days before Tomb Sweeping Day, the low mountains along the Ren River generally open two days before and after Tomb Sweeping Day, and the mountains above the middle level usually open after the Grain Rain Festival. During this period, the fresh leaves in the garden are "single buds" for the first time, or "one bud and one leaf." Tea growers call them "crow bird mouth," "flag gun," etc. Ziyang Tea Garden is located at an altitude of 350-900 meters. There is a 7-day time difference between the high and low mountains for spring tea picking. Most tea processed in the first ten days is high- to medium-grade. Tea leaves picked after ten days are generally medium and low-grade tea.

In the late 1980s, to seize the market, some tea farmers started picking before the spring equinox, which caused significant damage to the tea trees. The tea yield was low, and the processed tea leaves were delicate but dark in color and weak in fragrance. After this phenomenon occurred, the tea management department stipulated the spring tea picking time, prohibiting blind picking regardless of the season, and only tea buds were allowed to grow to a certain standard. Summer tea can be picked 20-30 days after spring tea is picked. Autumn tea picking can be done at any time according to the germination status of the tea tree. Later, the summer and autumn teas were picked in stages and multiple times, and 40 batches could be picked in spring, summer, and autumn. Ziyang tea picking standards can be roughly divided into four types: tender picking, moderate picking, mature picking, and unique picking. On October 11, 2007, Ziyang selenium-rich tea was integrated into two series of products, Ziyang Maojian and Ziyang green tea, and fresh picking standards for Ziyang Maojian, Ziyang green tea, and Ziyang sun-dried green tea were formulated. Ziyang Maojian particular grade stipulates eight no-picking rules: no picking on rainy days, no thin buds, no purple buds, no picking on wind-damaged buds, no picking on insect-damaged buds, no picking on happy buds, no picking on hollow buds, and no picking on diseased bent buds. Pick.

Ziyang tea picking techniques generally include timely picking according to standards, multiple pickings in batches, and reasonable leaf picking. The traditional custom of picking Ziyang summer and autumn tea has not entirely changed; that is, no or less tea is picked in summer and autumn. Manual tea picking is a traditional tea picking method in the Ziyang Tea Area. Picking tea is carried out by hand and divided into flowers. Machine picking is mainly suitable for bulk picking in tea gardens. The efficiency of machine picking is 20-50 times that of manual tea picking. The complete buds and leaves picked by machine can reach 60%-70%, and the production rate can get more than 90%. When machine picking is implemented, machine picking can be carried out when 80% of spring tea, 60% of summer tea, and 40% of autumn tea shoots meet the picking standards. The machine-picked batches are spring tea once, summer tea 1-2 times, and autumn tea 2-3 times. In 2004, as the area of tea gardens continued to grow and the number of migrant workers increased, the labor shortage in tea picking became increasingly prominent. The trial began to promote machine picking and simple manual tea-picking scissors were introduced to pick fresh leaves in tea gardens on slopes. Due to differences in tea garden management technology, the management level of some tea gardens cannot meet the standards and requirements of machine-picking. In addition, there is no emphasis on picking summer and autumn tea, and the promotion of machine-picking technology is slow.

Clean, well-ventilated bamboo or rattan tea baskets are generally used to hold the tea when picking fresh leaves. Non-ventilated cloth bags, plastic bags, and other utensils are not allowed. After the fresh leaves are harvested, they are spread flat in an excellent place to keep them fresh to prevent deterioration and are quickly transported to the tea factory for processing. During storage and transportation, machine-picked leaves and hand-picked leaves should be separated, raw materials of different tea tree varieties should be separated, sunny leaves should be separated from rainy leaves, regular leaves should be separated from deteriorated leaves, adult tea leaves should be separated from aging tea leaves, and leaves picked in the morning should be separated from those picked in the afternoon. The harvested leaves are separated for easy classification and packaging to prevent confusion of grades.

Ziyang selenium-rich tea is manually processed through drying and sorting, greening, initial kneading, stir-frying, re-kneading, baking, slicing, re-baking, dry roasting, and re-fire collection. In 1986, the County Science and Technology Commission and the County Tea Station jointly completed a research project on improving the quality of Ziyang Maojian. They won a special prize for scientific and technological achievements in the Ankang region. The manual processing of Ziyang tea changed. Since 1989, we have successively introduced electric woks from Zhejiang Fuyang Tea Machine Factory, hand-pushed twisting machines from Hubei Wufeng Tea Machine Factory, and electric type 30 and 35 famous tea twisting machines from Zhejiang Shangyang Tea Machine Factory, and started handmade tea processing. Quality is improved, and labor intensity is reduced. In the 1990s, Jiangsu and Shaanxi exchanged targeted poverty alleviation. Ziyang County sent farmer technicians to Zhejiang and Jiangsu to learn the manual processing technology of Longjing and Biluochun tea and hired tea technicians and farmers' tea-making experts from the two provinces to Ziyang for field training and on-site guidance. Tea technical cadres conducted technological transformation research and demonstrations, and the technical level of hand-made tea was improved. Biluochun tea processing technology was promoted mainly in Xiangyang Town and eventually expanded to Chengguan, Huangu, Donghe, Bajiao, Shuangqiao, and other townships (towns). The Longjing tea processing technology was mainly demonstrated in Jianghe Village of Xiangyang Town and Panlong Village of Hongchun Town and was eventually extended to 15 townships (towns) in the county. The hand-processed famous and bulk teas have won many awards in tea quality competitions in the Ankang region and Shaanxi Province. Famous teas are sold in tens of yuan for 500 grams to more than 300 yuan for 500 grams. Tea picking time and tea tree variety are the basic standards for processing high-end tea. The medium-leaf type has bud heads, the basic raw materials for processing Ziyang Maojian. Each kilogram of tea requires 18,000-24,000 bud heads; the small-leaf type has thin bud heads, the primary raw material for processing Ziyang Maojian. The primary raw material of Ziyang Biluochun is 32,000-38,000 buds per kilogram. Only about 500 grams of fresh leaves can be picked for each manual picking day.

In the late 1970s, 77 primary tea processing plants were established in the county. Due to inadequate site selection and equipment support, 48 companies could usually process. By 1995, only five primary processing plants in the county continued to produce. In 1998, we successively introduced famous and high-quality tea machinery from Zhejiang Shangyang and Fuyang Tea Machinery Factories to support the construction of well-known and high-quality tea machinery processing demonstration plants.

In 2001, farmers were mainly self-financed with appropriate subsidies from the state to introduce and install supporting small-scale, famous, and high-quality tea machinery. In 2005, 98 new famous and high-quality tea processing plants were built in the county, and for the first time, semi-mechanized processing was realized with Ziyang Maojian as the main body.

In 2006, tea machinery was included in the provincial agricultural machinery demonstration project and the scope of national agricultural machinery subsidies to promote the transformation of small processing plants into medium-sized processing plants. Ziyang Selenium-rich Tea Co., Ltd. used the funds from the southern Shaanxi Breakthrough Development Project to implement the construction of a tea processing system and build 15 new clean processing plants with an annual processing scale of 30 tons to 50 tons. It also built 60 standardized preliminary processing plants with an annual processing capacity of 30 tons. The designed processing capacity is 10 tons-15 tons, and a refining processing plant with a yearly output of 500 tons will be built through investment promotion.

In 2009, the county received a provincial agricultural machinery subsidy of 1.7837 million yuan and a provincial agricultural machinery demonstration project support of 220,000 yuan. It built 201 tea processing plants and owned 1,346 sets of machinery and equipment, including 14 standardized processing plants and the introduction of 13 clean processing production lines. , 60 primary tea processing plants, 127 famous tea processing plants, with a mechanical processing capacity of 2,500 tons and actual processing of 1,860 tons, accounting for 67.4% of the total annual output. The critical processing enterprises cultivated through selective support and support, the processing quality of famous tea has reached domestic standards, and the products have successively won the "China Tea Cup" special prize and the "Qinba Tea King" gold medal at the 7th China International Agricultural Products Fair.

By the end of 2010, more than 1,000 famous tea processing machinery were introduced, and 168 tea processing plants were built, including 60 standardized preliminary processing plants supporting 30 key enterprises and 14 clean processing plants. County Tea Research, The company introduced oolong tea processing machinery and sent people to Anxi County, Fujian Province, to study and successfully develop Ziyang selenium-rich oolong tea. Ziyang Minqin Tea Co., Ltd. has developed Ziyang selenium-rich black tea. The process flow and technology of mechanized processing of Ziyang's two series of selenium-rich tea products have matured and reached national standards.

Processing technology of Ziyang County Selenium-rich Maojian tea: Pick one bud and one leaf with young leaves before the Qingming Festival, and pick and make them now. Processing steps:

Use a flat pan for cooking, use dry firewood as fuel, the temperature of the pan reaches 150 degrees, add about 1500 grams of fresh leaves, and stir-fry with both hands first; when the buds and leaves are hot to the touch, use a wooden fork to continue stir-frying, the leaves will turn into emerald dark green. , the leaves are as soft as cotton, emit a green aroma, and can be spread out in thin sheets to distribute moisture and heat.

Initial kneading: After the green leaves have cooled, you can knead them for the first time. Place the tea leaves on a flat plate or in a basket, and twist them with your hands like a ball or in a dough-kneading manner. Be gentle first and then heavy. When the tea juice overflows, switch to gentle kneading and slowly turning. The middle will be lumped appropriately, and the tea leaves will form strips when spread out.

Initial drying: Spread the tea base thinly on a basket or drying mat to dry in a ventilated, dry, clean, and sanitary place. Avoid smoke. When it is half dry, you can knead it again.

Repeated kneading: Pinch the semi-dried tea into a hand towel, rotate your hands in different directions, and use the force of your palms to rub the tea leaves against each other until they are tightly rolled into strips, revealing the pekoe. Dry until the water content of the tea leaves is about 6%, and it becomes Ziyang Maojian.