Yes. Tea has caffeine in the range 2.5% to 5.5% on a dry weight analysis and these levels can vary through such factors as time of year, climatic conditions, type of clone, even in the manufacturing stages.
Green tea has about the same amount of caffeine as black tea but generally less green tea is used to make a cup so, on a per cup basis, green tea would probably have less.
There is a big difference in the amount of caffeine per cup of tea and coffee. Drip Filter coffee has up to 180 mg/cup, percolated up to 150 mg, instant 100 mg. A cup of tea has an average of 40 mg per cup(weak cup 30-strong cup 60).
Black tea is fermented, green tea is not. The leaf appearance, one is black, the other green. Black tea in the cup is a deep red, green tea is very light green or yellow. They taste totally different.
Polyphenols are part of the Flavonoid component of tea. The polyphenols are made up of the tea catechins and their gallates. They used to be referred to as the tea tannins. They are the antioxidants in tea.
The formula for Tea Tannins is C20 H20 09.
Tannic acid is used for the tanning of leather and is found in the bark of many plants and in some ferns. Commercial quantities of tannic acid are extracted from the bark of the Oak and American Chestnut trees. Generally, real tea does not contain tannic acid provided only the fresh tender leaves are harvested and there is no hard wood or bark used. Of course, herbal infusions and tea substitues are not real tea and could contain tannic acid.
The formula for Tannic acid is C14 H10 09.
Free Radicals are cells with only one electron instead of two. Free radicals are caused by UV rays, pollution, chemicals and smoking. The free radicals try to steal an electron from healthy cells and this activity is not good as it can lead to cell damage. The free radical can be neutralized by antioxidants which are contained in many fruits and vegetables and in very high quantities in tea.
There are essentially three methods of decaffeination, two of them are chemical and the other could be classed as natural. The most widely used is where a solvent called Methylene Chloride is used, the next is by using Ethyl Acetate. The natural method uses liquid carbon dioxide but this is not widely available. (Methylene Chloride is commonly used as a paint stripper and Ethyl Acetate in nail polish remover.
In those countries where insect pests are an issue, pesticides are used, both of the Organochlorine and Organophosphate types. Nowadays, producers avoid indiscriminate use. Typically, on a 2000 acre plantation, a small area of 5 acres may have a pest problem. The cycle of many pests is that damage is caused during the larvae stage, they have a feed, mature to adults, then move on. Because of the vigour of the newer clones the damage is shrugged off and the bush speedily recovers. The loss in crop is negligible and the use of costly chemicals and application costs often are a deterrent to their use. Maximum residual levels for pesticides have been laid down by the consumer countries but there is no uniformity between countries. Australia is amongst the world's most stringent.
Green tea has at least 3 times the antioxidants of black tea-but about twice the amount of leaves is used to make a cup of black tea so the antioxidants per cup of black is still quite high.
Tasters gauge a tea on leaf appearance,colour in the cup, taste, and brightness of the infused leaves.
The pulp and fibre used for tea bag paper manufacture used to be chlorine bleached but public pressure enabled the change to bubbling millions of tiny oxygen bubbles through the pulp to whiten it.
Tea catechins and polyphenols are part of the Flavonoids. The polyphenols, tea catechins and their gallates account for about 30% by weight of the composition of a tea shoot.
The polyphenols in tea can inhibit the uptake of non haem iron, that is, the iron derived from fruit and vegetables. A strict vegetarian should drink tea between meals rather than with meals. The phytates in Bran flour will also inhibit the uptake of iron.
Tea is a known aluminium accumulator but this is concentrated in the lower maintenance foliage the leaves of which are not used in the manufacture of tea.
The polyphenols contribute to the 'mouthfeel' of tea and caffeine too, in it's pure form, is a very bitter substance. A high proportion of each will give a bitter tea.
Tea should be stored in an airtight container. Light and moisture are the enemies of tea so a clear container in bright conditions will lead to deterioration. Storing in the Fridge is advocated by some but this can lead to condensation when removing the container and this will affect the tea.
Tea is blended to enable each packet of tea to taste consistently the same. Tea from a single plantation tastes different right throughout the year and leaf standard, time of year, length of daylight, rainfall, and other factors determine the changes in taste and flavour. By using complementary teas from different regions and countries with different characteristics, the blender is able to consistently maintain the characteristics of the final tea to be packed.
There are many kinds of tea. The main types of tea are Green Tea, Oolong Tea and Black tea. The types of manufacture are Orthodox, a gentle rolling and kneading of the leaf, and CTC , the severe crushing, tearing and curling of the leaf. Lesser known teas are snow tea, white tea, brick tea, black-black tea. Other than the main types of manufacture some producers use a Legg Cutter (a tobacco cutting machine) or an LTP (Lawrie Tea Processer-a giant hammer mill). Lo-Yu, who wrote his Cha Ching (tea book) in 750 AD stated there are a thousand teas and there are ten thousand teas.
The experts say that cups stain because of the calcium ions and carbonates in temporary hard water. Boiling the kettle for an extra few minutes will get rid of these if you do not have a de-ionizer. A drop of lemon will prevent staining. We have found that the condition of the glaze in the cup plays its part in staining too.
Research is accumulating evidence in clinical trials that tea has a beneficial effect on health but until everything is conclusively proven one is restricted on what can be said about the health benefits of tea.
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Yes. Unblended teas are not necessarily better than blended ones. Specific Origin teas would consist of a number of teas from one country, mixed together. E.g. pure Indian-pure Ceylon. Single Estate teas are the only unblended teas but their quality is only at its best at certain brief times of the year, and as a consequence they become very expensive at this time. Outside of these periods the quality of single estate tea can be fairly ordinary.
Water temperature is important-water just on the boil for black tea - water well off the boil (about 70 deg C) for green tea.
The first tea bag was made by Thomas Sullivan. In 1908. The first mechanically packed teabags were on a Pompadour machine in 1929.
The name Madura is taken from the 16th century Great Temple of Madura, in the Madurai district of Tamil Nadu in South India. Madura, in the Tamil language, means "heaven" or "paradise".
Tea will deteriorate with age. Ideal storage conditions are said to be 20 deg C with a relative humidity of 35%- at which the tea will not dry out or absorb moisture. These conditions are rarely met. Even if teas were stored under ideal conditions there is a very slow process that continues, called post oxidative reaction, that is, the tea continues to ferment. As stated, it is a very, very, slow process but if stored for a couple of years, where it can access air, it will change in taste. Some packers, like Madura, vacuum pack and nitrogen flush the packets, and this is probably the very best protection that can be given.
Dust will sometimes sell at an auction for a higher price than leaf tea. Dust grades are the smallest particles sifted out of the made tea. A dust tea will brew up much stronger, thicker and more astringent than a leaf tea.
The flavouring in Earl Grey is Bergamot, from the Citrus Bergamia the fruit of which looks like a small grapefruit. Most Bergamot is grown and produced in Calabria in Southern Italy.
An oolong tea is one that has only been partly fermented.
Papaya (Paw Paw) leaf contains an enzyme called 'papain' and this is useful for clearing undigested protein in the gut. Many other claims about the benefits of papaya are made but everyones metabolism is different and what might seem like a miracle drink to one may have little or no affect on another.
The smaller the particle size, the quicker and stronger the brew. Large whole leaf teas tend to brew slower and lighter than small leaf teas.
The tea bush has a dainty white flower carried singly or in bracts. It has a delicate perfume.
Mechanical harvesting will not be as good as a good hand plucker BUT there are an awful lot of bad pluckers about. Some Estates are well behind on pruning cycles and sometimes the hand plucker can only reach the top of the bush with difficulty not seeing the leaf and tearing it off in handfuls rather than seeing each shoot clearly and snapping it off. Tea pickers in most of the large tea estates around the world are paid on a piece rate. This is hardly an incentive to consistently picking only "the two leaves and the bud".
A tea bush will live for thousands of years. A tea bush is commercially productive for about 30 years. As better and better plants are released the time frame for replacement of older tea is determined by the producers.
Tea is grown from seed, cuttings and tissue culture. In 1933, Mr A.C.Tunstall developed the method of vegetative propagation using single leaf internode cuttings-now widely practiced all over the tea growing world. Madura Tea participated in an Australian based project which successfully resulted in tea being propogated via tissue culture techniques.
The fact that caffeine is very soluble in hot water means that you can do your own caffeine reduction: dip the tea bag in a cup of boiling water for 20-30 seconds. Remove the teabag and discard the cup contents. Brew again using the partially used teabag and allow to infuse until the desired colour is reached. Result: less than 1% caffeine in that cup. Useful to do this during pregnancy. Madura tea, through frequent testing, enables us to use teas that are in the low caffeine range and thereby consistently maintaining levels at 2.8%, which is at the lower end of the caffeine scale.
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