Important for the taste of green tea are the amino acids in the tea leaves, especially the theanine . Amino acids make up to six percent of the dry weight of tea leaves. The content of amino acids can be selectively increase the cultivation by the shaded tea plants in the spring.
Other ingredients are Vitamin A , Vitamin B , B2 , calcium , potassium , phosphoric acid , magnesium , copper , zinc , nickel , carotenes and fluoride . Certain ingredients fall for the absorption is not significant.
Green tea contains more tannins ( tannins ) than black tea . Therefore it tastes bitter as this. The tannins act with nervous stomach and intestinal soothing and astringent with sluggish bowel.
Japan (selection, alphabetically)
- Aracha (Japanese:荒茶), raw green tea
- Bancha ("ordinary tea", Japanese:番茶), similar to Sencha (older leaves), low caffeine content, much calcium is harvested in all tea growing regions of Japan from the same plant as the Sencha, in contrast to this (plucking only the leaf- bud and the first two leaves) is picked fourth, fifth and sixth leaf. Therefore it is a simple tea and contains little caffeine because the young leaves contain more caffeine and result in better qualities.
- Fukamushicha (more damped Sencha, Japanese:深蒸し茶)
- Funmatsucha (Instant ground tea, Japanese:粉末茶)
- Gabalong (Japanese:ギャバロン茶), high gamma-amino acid content obtained by special processing natural
- Genmaicha (Japanese:玄米茶), enriched with roasted rice and thereby flavored tea
- Gyokuro ("noble Dewdrop", Japanese:玉露) Schattentee, grassy, high caffeine content
- Hojicha , (Japanese:焙じ茶) roasted Sencha / Bancha
- Kabusecha (under the penumbra network grown tea, Japanese:かぶせ茶), a sencha, growing under similar light conditions as the wild tea plant
- Kamairicha (roasted tea, Japanese:窑煎茶)
- Konacha (Japanese:粉茶)
- Kukicha (Japanese:茎茶), high proportion of stems and leaf ribs, grassy, needle-shaped leaf, mild and koffeinarm
- Matcha ("ground tea", Japanese:抹茶), powdered Schattentee from Tencha (Basistee), high caffeine content
- Mecha (Japanese:芽茶)
- Sencha ("steamed tea", Japanese:煎茶), the most widely drunk green tea in Japan, there are various qualities of three harvest seasons (April / May first harvest in June / July, second crop, August / September-third harvest). The earlier the harvest, the higher the quality, however, depends not only on the harvest time.
- Shincha (new tea, Japanese:新茶)
- Tamaryokucha (Japanese:玉绿茶), another form of roasted or steamed teas, Variant: Yonkon
- Tencha (Japanese:碾茶)
China (selection, alphabetically)
- Bi Feng, fine leaf
- Cris Cross, soft leaf tea with jade-green color
- Ching-cheng, Sichuan Province
- Chun Mee ("precious eyebrow"), curved silvery sheet, strong, slightly smoky
- Gunpowder ("Gunpowder"), tea leaves rolled into balls, bitter
- Gu Zhan Mao Jian
- Gui Hua
- Li Zi Xiang, golden tea
- Long Tseng, long, flat blade
- Lung Ching or Longjing ("Dragon Well tea," often referred to as "dragon tea", the translation of "Dragon Well" is correct), from province of Zhejiang , flat green leaves, jade green color, spicy, clear in infusion and yellow
- Feng Mao (Mao = hairy, Feng = pointed), tea from the high mountains, gently twisted silvery leaves
- Mao Feng Cris Cross is called a noble rarity in infusion yellow-green cup with sweet fine nuances
- Mao Jian ("hair tips")
- Matcha (ground coffee), powdered Schattentee, rich in EGCG catechins and caffeine
- Mêng-Ting (Hidden Peak)
- Moon Palace, spherical leaf, slightly tart flavor
- Pan Long Ying Hao, soft, rolled leaf with many white Teespitzen
- Pi Lo Chun, deep green and finely twisted leaf, fresh aroma, bright in the infusion
- Pouchong (Taiwan), fruity aroma
- San Juan Xia Mao, slightly curled leaf
- Sencha, bright and soft, yet spicy
- Tian Mu Qing Ding, finely crafted tea leaf, jade green in the infusion
- Tung-Ting, from Taiwan
- Tuocha, easy Yunnan fermented, spicy
- Yin Gou, uniform leaf surrounded by soft downy
- Yong Xi Hou Qing, raised by wild tea plants orchids between fields
- Yuncui is described as full-bodied, flowery, aromatic, hand-crafted, long deep green leaves
- Yunnan green, mild, light flavor
- Nilgiri fragrant, light citrus notes
- Assam strong, malty
- Darjeeling Muscatel note. First Flush: light cup, slightly tangy, fresh, reminiscent of asparagus. Second Flush: Strong cup with typical muscatel note
Medical effects and studies
Some other studies provide evidence that regular consumption of green tea, the risk of cancer of suffering, may decrease because in parts of the world where a lot of tea drinking, the incidence of certain cancers lower than in the rest of the world. For a preventive effect in particular are naturally present in some teas are polyphenols (particularly the epigallocatechin gallate, EGCG) blamed. The German Cancer Aid since 2011 promotes a long-term study at the Universities of Halle (Saale) and Ulm to effect against colon cancer with a total of 2.1 million euros.
A study in patients with prostate cancer , at the Center for Human Nutrition at the David Geffen School of Medicine of UCLA, was carried out, could show that the native of the tea EGCG was found in tumors and cell growth inhibited. The results indicate that green tea and black tea may help to prevent prostate cancer.
The polyphenols present in black tea and green tea in particular fluorides reduce the risk of dental caries .
If you drink more than ten cups of green tea a day, so that could damage his liver and kidneys. This claim Chung Yang and his colleagues at Rutgers University in New Jersey in the journal Chemical Research in Toxicology after a sighting of studies. To high doses of polyphenols present in green tea may be toxic, said Yang. However, to date this hypothesis could not be confirmed in human studies.
In another Japanese study has shown that both green tea and rooibos tea (rooibos tea) a prophylactic effect against diabetic nephropathy show. It is thought that the polyphenols present in green tea, or the present in rooibos flavonoids , free radical trap. This is possibly the addition of glucose to the body's own proteins (the so-called Maillard reaction ) is reduced, so that the kidney is effectively protected. Diabetic nephropathy is due to diabetes mellitus induced kidney disease. It is a common cause of renal failure in diabetic patients.
Huntington's disease is an inherited, neuro-degenerative disease. On model organisms, it was found that green tea has the disease leading to plaque formation may be delayed. Responsible for the substance of EGCG extracted from green tea. It is able to retard agglomeration of the so-called Huntington protein. transgenic flies which the Huntington gene has been transferred, also showed improved flexibility after ingestion of EGCG.
The Egyptian scientist Dr. Mervat Kassem found that antibiotics appear much better if the patients also drink green tea. His research team tested the effect of this combination on the pathogens of infectious diseases 28. The green tea enhanced the effect in all cases. Even some bacteria that no longer respond to antibiotics, were again attacked.
Neurodegenerative diseases such as Alzheimer's and Parkinson's are caused by the formation of amyloid fibrils. The substance contained in green tea EGCG prevents their formation by binding to the native, still unfolded polypeptide chains. Thus, instead of the spherical-toxic, harmless fibrous amyloid fibrils, oligomers formed.
Moreover, studies show the multiple sclerosis research suggests that EGCG both nerve cells in the central nervous system to protect against damage and misguided T lymphocytes can that be blamed for the disease, regulate. Thus, the course was experimental autoimmune encephalomyelitis the animal model of multiple sclerosis - - on administration of EGCG significantly milder than in animals that did not receive EGCG. To achieve the doses used in the studies by consumption of green tea, but you would have to take large amounts of the day to himself.
By the addition of milk falls calcium oxalate as a sparingly soluble salt and is excreted via the gastrointestinal tract. The risk of kidney stone formation is thus reduced. However, a study shows led by Verena Stangl (Charité Berlin) that the caseins in the milk of the vascular protective, anti-inflammatory and antioxidant activity of catechins neutralize (such as EGCG).
World is now compared in over 100 clinical trials with green tea's medicinal effectiveness. However, many studies are difficult to compare. A variety of studies has now shown that regular consumption of green tea or green tea extracts has many health-promoting and preventive effects. Many of these positive effects on obesity , diabetes , inflammation, Parkinson's , Alzheimer's and heart disease resulting from or in green tea extracts, plentiful particularly epigallocatechin gallate (EGCG).
In addition, researchers at the University in West Lafayette have found that a shot with something sour like lemon in green tea and vitamin C, the so-called antioxidants - especially catechin - get in the tea helps so they do not disintegrate already in digestion. So they can be better absorbed by the body. Orange, lime and grapefruit juice has the same effect as adding.
It was shown that EGCG to the entrance hepatitis C virus in the liver could prevent cell in laboratory experiments. Studies on humans are not yet available.
How to prepare green tea?
When brewing green tea water should be used with a maximum temperature of 90 ° C because of hot water makes the tea bitter and inedible depending on variety. Colder than 50 ° C, the water should not be. With increasing temperature, the solubility of most improved tea components - the drawing of water is too cold, then the valuable contents can not be dissolved in the infusion. Many varieties are 70 ° C at the right temperature for making tea. However, the decision also subjective taste.
In East Asia, the tea leaves are left in the water longer. The taste will change over time as the drinking, resulting in a very bitter Teerest after 10 minutes of infusion. The pouring into a second, empty can is not common in China. Chinese restaurants like to practice the coating, not Korean.
You can green tea to infuse two-three times. However, be noted that in further infusions the infusion time should be shorter. There are tea drinkers who say that the second infusion taste better than the first. To the infusions but must be prepared properly. This implies also an old saying: The first cup for the enemy - the second cup for the friend.
The tea culture in North-West Africa three infusions are standard practice in the variety Gunpowder. This abundant sugar and often get some fresh Nanaminzeblätter into the teapot. The tea should be poured from a great height into the glasses or transferred more than once to get the desired foam forms in the glass.