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What is tea?
Where did the name 'tea' come from?
What are the different kinds of tea?
How is tea produced?
Why is Ceylon Tea different?
How much caffeine is there in tea ?
How much caffeine is considered safe?
Does green tea have the same Caffeine level as black tea?
Why should one never reboil water when brewing tea?
Does drinking tea during pregnancy affect the foetus?
What is decaffeinated tea ?
Tannic acid – what is it and is it present in tea?
What are the nutritional benefits of tea?
Does tea affect the absorption of Iron?
What are antioxidants?
Are the antioxidants in green and black tea the same?
Can the consumption of tea be good for my memory as I grow older?
Is regular tea consumption good for my immune system?
Can tea be part of a healthy adult's daily fluid intake?
Does tea reduces the diuretic effect in comparison to coffee?
Why does tea cloud when it is cooled?
Does the water affect the tea brew?
What is tea scum or the dark skin on top of the brewed tea?
Can overcooked water affect the quality of tea?
What is Real Tea?
What are Herbal Infusions?
When Tea is not TEA
What is White Tea?
What is tea?
Tea is a drink made by infusing leaves of the tea plant (Camellia sinensis, or Thea
sinensis) in hot water. The name 'tea' is also used to refer to the leaves themselves;
and it is also the name of a mid- to late-afternoon meal in the British Isles and
associated countries, at which tea (the drink) is served along with various foods.
Where did the name 'tea' come from?
The word for tea in most of mainland China (and also in Japan ) is 'cha'. (Hence
its frequency in names of Japanese teas: Sencha, Hojicha, etc.) But the word for
tea in Fujian province is 'te' (pronounced approximately 'tay'). As luck would have
it, the first mass marketers of tea in the West were the Dutch, whose contacts were
in Fujian . They adopted this name, and handed it on to most other European countries.
The two exceptions are Russia and Portugal , who had independent trade links to
China . The Portuguese call it 'cha', the Russians 'chai'. Other areas (such as
Turkey , South Asia and the Arab countries) have some version of 'chai' or 'shai'.
'Tay' was the pronunciation when the word first entered English, and it still is
in Scotland and Ireland . For unknown reasons, at some time in the early eighteenth
century the English changed their pronunciation to 'tee'. Virtually every other
European language, however, retains the original pronunciation of 'tay'.
What are the different kinds of tea?
The three main categories are green, black, and oolong. All three kinds are made
from the same plant species. The major differences between them are a result of
the different processing methods they undergo. Black teas undergo several hours
of oxidation in their preparation for market; oolongs receive less oxidation, and
green teas are not oxidized at all.
There are, of course, many different varieties within these three main categories.
How is tea produced?
The first step in tea production is the harvest. Most harvesting is still done by
hand, which (as you can imagine) is very labor-intensive. Some growers have had
success using a machine that acts much like a vacuum cleaner, sucking the leaves
off the branch. The latter method is used for the cheaper varieties of tea, as it
is not capable of discriminating between the high-quality tip leaves and the coarser
leaves toward the bottom of the branch.
The harvested leaves can be processed in two ways: CTC or orthodox.
CTC, which stands for "crush, tear, curl," is used primarily for lower-quality leaves.
CTC processing is done by machine; its name is actually fairly descriptive. The
machines rapidly compress withered tea leaves, forcing out most of their sap; they
then tear the leaves and curl them tightly into balls that look something like instant
coffee crystals. The leaves are then "fired," or dehydrated.
Most tea connoisseurs are not very interested in CTC tea, since this process does
not allow for the careful treatment that high-quality leaves merit. But CTC has
an important and legitimate role in the tea industry: since it is a mechanized process,
it allows for the rapid processing of a high volume of leaves which otherwise would
go to waste. It is also good for producing a strong, robust flavor from leaves of
middling quality; in fact, for many varieties of leaf CTC is the preferred processing
method.
The orthodox method is a bit more complex, and is usually done mostly by hand. The
process differs for black, green, and oolong teas. The basic steps in the production
of black tea are withering, rolling, oxidation, and firing.
First, the leaves are spread out in the open (preferably in the shade) until they
wither and become limp. This is so that they can be rolled without breaking.
Rolling is the next step. This is rarely done by hand any more; it is more often
done by machine. Rolling helps mix together a variety of chemicals found naturally
within the leaves, enhancing oxidation. After rolling, the clumped leaves are broken
up and set to oxidize.
Oxidation, which starts during rolling, is allowed to proceed for an amount of time
that depends on the variety of leaf. Longer oxidation usually produces a less flavorful
but more pungent tea. Many texts refer to the oxidation process by the misleading
term "fermentation." However traditional and evocative the term may be, I think
it is best avoided. Oxidation of tea leaves is a purely chemical process and has
nothing to do with the yeast-based fermentation that produces bread or beer.
Finally, the leaves are heated, or "fired," to end the oxidation process and dehydrate
them so that they can be stored.
Oolong is produced just like black tea, except that the leaves are oxidized for
less time.
Green tea is not oxidized at all. Some varieties are not even withered, but are
simply harvested, fired, and shipped out.
Why is Ceylon Tea different?
Tea originated in China , as legend has it, 5,000 years ago, yet it was Ceylon (now
Sri Lanka ) that made tea famous in the 19th and 20th Centuries, as the tea that
was used by almost every major tea brand. Ceylon Tea is prized for its quality which
is without parallel, and its variety which is unmatched for a small island boasting
dramatically different teas in different parts of its tea growing regions.
In assessing the value of Ceylon tea, some of the properties which tea experts take
into consideration are appearance of the made tea, colour of the infused leaf, as
well as colour, strength, quality, aroma and flavour of the brewed liquor. The ultimate
criterion of a 'good quality' tea is however the the subjective assessment of expert
professional tea tasters.
Distinguishing itself as the 'Best in Class' producer of tea, with a well documented
heritage in tea, Ceylon , or Sri Lanka stands out amongst tea producers. The Low
Grown teas produced in Sri Lanka below 2000-ft sea level, are known for their superior
leaf appearance, highly valued in the Middle East , the coppery 'infused leaf' and
its strong & reddish brewed liquor. Sri Lankan low growns are prized for their
appearance -'uniformly black', true to grade and devoid of fibre and extraneous
matter. The High Growns, above 4000-ft sea level, on the other hand are known for
their bright, coloury, brisk and aromatic liquors. High grown Ceylon teas do not
share the dense, black colour of the quality low grown leaf being browner in leaf
appearance, but have unsurpassed liquors ranging from light, bright golden colour
to deep red.
In Ceylon , particular emphasis is laid on the quality of tea, and this is determined
by a complex of parameters, the correct balance of which is the quintessence of
tea character. The appearance of the leaf (dry leaf after processing) is determined
by the content of chlorophyll in the young and tender leaves of the tea shoot. The
relative amounts of the polyphenols present in tea, the polyphenol oxidase (enzyme),
the theaflavins, thearubigins, caffeine, essential oils, sugars, amino acids in
the bud and the first two tender leaves will all contribute to the quality of the
brewed liquor in a positive way. Hence the importance of traditional and disciplined
picking of teas in Ceylon . The best raw material handled under poor conditions
of manufacture would produce a poor quality tea. It is through attention to detail
in field practices as well as in manufacture, that Sri Lanka retains its position
as the Best in Class' producer of Quality Tea, considered by the Technical Committee
of the ISO as the cleanest tea in the world.
How much caffeine is there in tea ?
Caffeine from natural sources has been consumed and enjoyed by humans throughout
the world for centuries. The widespread natural occurrence of caffeine in a variety
of plants undoubtedly played a major role in the long-standing popularity of caffeine
incorporated products, especially the beverages.
The human body requires a certain amount of caffeine and research indicates that
up to 10 - 12 cups of tea daily will not have any detrimental effect on the body.
The species or the variety of the tea plant determines content of caffeine in tea,
as it is a genetic feature. Camellia Sinensis, the variety that is grown in Sri
Lanka has caffeine levels of approximately 2.5 - 4%. However the distribution of
caffeine in the plant depends on the part of the plant it is derived from.
For example:
- Bud 4.70 %
- First leaf 4.20 %
- Second Leaf 3.50 %
- Third Leaf 2.90 %
- Upper stem 2.50 %
- Lower stem 1.40 %
Both tea and coffee contain the methylated xanthines, caffeine, theophylline and
theobromine. Brewed coffee is said to have the highest caffeine content among those
dietary items containing caffeine- approx. 100 mg per cup. A 300-ml bottle of cola
has 30- 60-mg caffeine and approx. 37-mg caffeine is there in 56g dark chocolate
bar. There are a wide variety of drug products that contain caffeine- typically
200 mg per tablet or capsule (pharmacologically active dose of caffeine). A cup
of tea has approx. 28 –44 mg caffeine- (FDA 1980).
The quantity of caffeine in tea, on dry solids basis, is more than the quantity
of caffeine in an equal weight of dried coffee beans. However, as a result of getting
more cups of tea from a unit quantity of black tea than from an equal quantity of
ground coffee beans, the quantity of caffeine per cup of tea is less than the caffeine
in an equal cup of coffee.
Excessive caffeine is said to have adverse effects on the human system and brewed
tea has only half the caffeine levels in brewed coffee. However, it is important
to note that research proves that the presence of caffeine in tea does not produce
unhealthy results due to its combination with tea polyphenols.
How much caffeine is considered safe?
The Food Guide to healthy eating recommends caffeine consumption in moderation.
According to the current findings for most people an intake of caffeine up to 400-450
mg per day does not increase the risk of heart disease, hypertension or have an
adverse effect on pregnancy or the foetus. This level of caffeine is equivalent
to approximately 10 to 12 cups (170 ml) of tea per day.
As explained by Prof. T. W. Wickremanayake (Ph D Glasgow, Visiting Research Fellow
Glasgow, Wisconsin and California ) the pharmacologically active dose of caffeine
is 200 mg and the acute fatal dose is about 10,000 mg. Those who drink more than
5 cups of coffee or 9 cups of tea are regularly consuming 5% of the fatal dose.
The T 1/2 of caffeine is about 3 hr. It is excreted quickly in urine as 1-methyl
uric acid.
Prof. Wickramanayake also states the following. “There is a positive association
between Myocardial infarction and heavy coffee consumption, whereas the correlation
between infarction and heavy tea drinking is negative. In rats and rabbits maintained
on atherogenic diets, caffeine increases serum lipid concentrations and therefore
the incidence of atherosclerosis. Coffee has the same action but not decaffeinated
coffee. Tea has the opposite effect to caffeine alone or caffeine in coffee. Similar
results have been reported in a study of human subjects with and without heart ailments.
Russian scientists have demonstrated that a course of tea consumption improved the
condition of atherosclerotic patients. The alleged adverse effects of caffeine are
apparently eliminated in tea either by a modification of its activity by other constituents,
or by the opposing action of some anti-atherosclerotic constituent."
Does green tea have the same Caffeine level as black tea?
Green tea, as well as Oolong tea & Black tea, are produced from the herb Camellia
Sinensis. They all contain the same amount of caffeine. Caffeine content in a cup
of tea is 2.5% to 4%, which is about a third of that in coffee. It is claimed that
80% of the caffeine in tea remains unabsorbed by the human body.
From the above you would realise that Green tea, Oolong tea & Black tea may
taste different but the caffeine content is the same.
Why should one never reboil water when brewing tea?
Taste, colour and mouth feel depend on the interaction between the two main components
of tea, polyphenols and caffeine. Each component is astringent on its own, but as
a complex the astringent character is reduced.
Water is known to contain dissolved gases absorbed from the air. Carbon dioxide
(CO2) gas that is present in water affects the acidity. Acidity of water plays a
critical roll in the ionization of tea polyphenols and it contributes to the stability
of the above complex.
CO2 in water is gradually released during the boiling process. Re-boiling will in
fact further reduce CO2 levels, resulting in a decrease in the acidity. As mentioned
above this will affect the caffeine and polyphenol complexion, and bring about changes
in the colour as well as the character of the brew.
Twice boiled water will therefore affect the taste of a good tea and hence our request
that only freshly boiled water is used for brewing Girnar tea.
Does drinking tea during pregnancy affect the foetus?
Questions surrounding caffeine intake and risk of miscarriage and health of the
foetus continue to be raised by pregnant women.
A study published in the journal of American Medical Association found no evidence
that moderate caffeine use increases the risk of spontaneous abortions, growth retention
or account for other factors. Another seven-year epidemiological study on 1,500
women examined the effect of caffeine, during pregnancy as well as on subsequent
child development.
Caffeine consumption equivalent to approximately 3 ½ to 5 cups of tea per day had
no effect on birth weight, birth length and head circumference of the baby. A follow-up
examinations at age's eight months, four and seven years also revealed no effect
of caffeine consumption on the child's motor development or intelligence.
A number of factors influence the metabolism of caffeine and the individual's response
to caffeine indigestion. These include pregnancy, age, sex, body weight, diet, exercise,
and stress smoking and alcohol consumption.
Pregnancy hampers caffeine metabolism. For example, in non pregnant women the break-down
of half of the caffeine takes an average of 2.5 - 4.5 hours, 7 hours during mid-pregnancy
and 10.5 during the last few weeks of pregnancy. As caffeine retention is longer
during pregnancy, women sensitive to caffeine may be affected. As a result a moderate
consumption of approximately 3-4 cups a day, is recommended for women during pregnancy.
What is decaffeinated tea ?
For teas to be labelled decaffeinated, the caffeine content should not exceed 0.4%
by dry weight, which is equivalent to approximately 4 mg of caffeine per 170 ml
serving.
The process of decaffeination extracts the caffeine in tea. The current commercially
available methods for decaffeinating black tea are solvent based extraction using
ethyl acetate or methylene chloride, and extraction using supercritical (solid)
carbon dioxide. All three methods extract caffeine with minimum effect to the quality
of tea.
Tannic acid – what is it and is it present in tea?
Tannins or tannic acid are not present in tea. Tea polyphenols were formerly referred
to as tannins or tannic acids due to the similarities in the chemical structure.
This has left many misguided notions about the effect of tea upon the human digestive
system. Chemists generally group compounds into ‘families' on account of common
features in the synthesis of the molecules. For example both strychnine and morphine
are alkaloids and have common structural features but the action on the human body
is different. Strychnine is a powerful stimulant and morphine a powerful hypnotic.
Vegetable tannins are a large chemical family and some of them are loosely called
tannic acids. These compounds possess the property of hardening animal tissues and
turning hide into leather. Tea polyphenols on the other hand are called catechins,
theaflavins and thearubigens, and are responsible for many of the health benefits
associated with tea. Such as anti-hypercholestemic action, anti-hyperglycemic action,
fat reduction action, anti-hypertensive action, anti- cancer action and many other
health promoting effects. Current scientific literature points to the fact that
tea polyphenols are biochemically very different to tannins.
What are the nutritional benefits of tea?
Tea composition varies with climate, season, horticultural practices and variety.
Polyphenols are the most important component in tea, as they constitute approximately
36 percent of the dry weight of tea. Other components of fresh green leaf include
caffeine, protein and amino acids, carbohydrates, lipids, vitamins and minerals.
Green and black tea have similar chemical make-up. The primary difference between
the two types lies in the chemical changes that take place during their production.
In black tea the plant Polyphenols are oxidized and this is prevented in the manufacture
of green tea.
One of the most important groups of Polyphenols in tea is the catechins in green
tea, theaflavins and thearubigens in black tea. A variety of physiological effects
have been attributed to tea catechins which are currently best known for their antioxidant
activities.
Black tea is all-natural (non flavoured) and contains no additives. It is virtually
calorie-free (1 calorie per 100 ml) and sodium free and is therefore a suitable
beverage for individuals on calorie-reduced or low sodium diet. Tea includes fluoride,
traces of vitamins A, K, C, B carotene and B vitamins.
Average daily consumption of tea in the United Kingdom , 3.43 cups (650 ml), provides
very few calories and only a small amount of fat, whilst contributing valuable minerals
and vitamins to the diet. It provides:
- Over half of the total intake of dietary flavonoids.
- Nearly 16% of the daily requirement of calcium
- Almost 10% of the daily requirement of zinc
- Over 10% of the folic acid need
- Around 9%, 25% and 6% of vitamins B1, B2 and B6 respectively.
Does tea affect the absorption of Iron?
Although concerns have been expressed about consumption of iron, existing research
and dietary knowledge indicate that tea is not likely to cause health risk, in individuals
consuming a typically Western diet.
Dietary iron exists in two forms, heme iron (derived from animal) and non-heme iron
(found in plants). The body better absorbs heme iron than non-heme iron. Between
15-35 % of heme iron is absorbed, while 2-20% is absorbed of non-heme iron. Non-heme
iron is generally modified by other dietary components.
Certain components in grain, fruit and vegetables as well as polyphenols in tea
reduce the availability of iron to the body. However, studies have shown that tea
only decreases iron absorption when it is consumed simultaneously with food containing
non-heme iron. Tea drinking between meals has no effect on iron absorption.
Moreover the ability of tea polyphenols to decrease iron absorption is reduced by
the presence of other dietary constituents particular ascorbic acid (known to increase
absorption of non-heme iron) and milk.
What are antioxidants?
Antioxidants are components which help to protect cells from harmful “free radicals”,
known as oxidants. Free radicals occur naturally in the body as a by-product of
the respiration process and can bring about cell damage. Antioxidants help to prevent
this cell damage, which can contribute to ageing and a number of chronic diseases,
including cancer and heart disease and strokes
.
Are the antioxidants in green and black tea the same?
It was thought until comparatively recently that green tea was the most effective
antioxidant-containing tea and that green-tea catechins (the unoxidized polyphenols
present in tea leaf) alone were the antioxidants giving tea its health-giving attributes.
It is now well known that the theaflavins and thearubugins produced by the condensation
of oxidized catechins, during the fermentation stage of black tea manufacture, are
equally effective antioxidants (Leung et al 2001).
The catechins present in tea flush and as such in green tea are
:Expressed as a % of dry weight
- Epicatechin 1 - 3%
- Epicatechin gallate 3 - 6%
- Epigallocatechin 3 - 6%
- Epigallocatechin gallate 9 -13%
- Catechin 1 - 2%
- Gallocatechin 3 - 4%
During manufacture of Black Tea these catechins get oxidized & polymerized (condensed),
for example :
Epicatechin + Epigallocatechin gallate + Oxygen ---> Theaflavin
The paired catechins as they appear in Black Tea are now known to be equally effective
antioxidants. The body produces free radicals (FRs) under certain conditions. Carcinogens
and radiation from the environment facilitates the formation of FRs. These FRs within
the body cause oxidative changes to DNA (the genetic material present in all cells).
Changes to DNA carry the risk of cancers. The FRs are inhibited and destroyed by
the antioxidants in tea, both green and black tea.
Green and black tea comes from Camellia Sinensis. Green tea is unfermented, steamed
immediately after plucking, and retains a lighter colour and flavour. Black tea
is allowed to ferment and is then dried, resulting in a darker leaf colour and a
more flavour and aroma.
Can the consumption of tea be good for my memory as I grow older?
Research conducted at the University of Newcastle shows that drinking tea could
help improve memory and also slow the development of Alzheimer's disease.
The functioning of the brain cholinergic system, which is involved in attention
and memory declines during normal aging and is further affected in Alzheimer's disease.
Current drugs for the symptomatic treatment of dementia are aimed at enhancing the
associated cholinergic deficit by inhibiting acetylcholinesterase, an enzyme that
cleaves the neurotransmitter acetylcholine. Butyrylcholinesterase increases in the
brains of people with Alzheimer's disease and may play a role in the progression
of the disease by its ability inter alia to hydrolyse the neurotransmitter Acetylcholine.
Inhibition of both these enzymes is one of the objectives in treating cognitive
dysfunction associated with diseases such as Alzheimer's disease.
During the study it was found both green and black tea inhibited the activity of
the enzyme acetylcholinesterase, and also hinder the activity of the enzyme butyrylcholinesterase.
It was further observed that Green tea obstructed the activity of beta-secretase,
which plays a role in production of protein deposits in the brain that are associated
with Alzheimer's disease. So this study reports that tea infusions in vitro have
dual anti-cholinesterase and anti-ß-secretase activities relevant to the treatment
of dementia.
Previous studies have shown that both green tea and black tea possess pharmacologically
protective, properties such as antioxidative, anticarcinogenic, neuroprotective
and hyppocholesterolaemic effects. This study indicates that Tea, Camellia sinensis
has the potential to enhance cholinergic function and therefore may have a role
in ameliorating and cholinergic deficit in Alzheimer's disease and other age related
memory impairments. The effects of tea infusions on the cerebral cholinergic system
and ß-secretase in vivo will depend on the levels of the enzymes in the brain, the
type and chemistry of the tea, infusion concentration (strength), dose (number of
cups per day) and duration of consumption. It is also possible that regular consumption
of tea by patients with dementia prescribed cholinesterase inhibitors may alter
the effects of such drugs. Clinical and scientific investigation of the chemistry
and activities of cholinomimetic and anti- ß-secretase compounds in C. sinensis,
and cognitive effects of tea consumption is warranted in order to establish the
relevance of these novel findings to the maintenance of cognitive function in old
age and in diseases such as Alzheimer's Disease.
Is regular tea consumption good for my immune system?
A Harvard Medical School study discovered that regular consumption of tea could
boost the body's defenses against infection. A component in tea was found in laboratory
experiments to prime the immune system to attack invading bacteria, viruses and
fungi, according to a study in the Proceedings of the National Academy of Sciences.
A second experiment, using human volunteers, showed that immune system blood cells
from tea drinkers responded five times faster to germs than did the blood cells
of coffee drinkers. Researchers claim that the results give clear proof that five
cups of tea a day sharpen the body's disease defenses.
In the study a substance called L-theanine was isolated from ordinary black tea.
L-theanine is broken down in the liver to ethylamine, a molecule that primes the
response of an immune system element called the gamma-delta T cell, considered the
first line of defence against bacteria, viral, fungal and parasitic infections.
The T cells prompt the secretion of interferon, a key part of the body's chemical
defense against infection. To further test the finding, the researchers had 11 volunteers
drink five cups a day of tea, and 10 others drink coffee. Before the test began,
they drew blood samples from all 21 test subjects.
After four weeks, they took more blood from the tea drinkers and then exposed that
blood to the bacteria called E-coli. The immune cells in the specimens secreted
five times more interferon than did blood cells from the same subjects before the
weeks of tea drinking researchers claimed. Blood tests and bacteria challenges showed
there was no change in the interferon levels of the coffee drinkers.
Can tea be part of a healthy adult's daily fluid intake?
As brewed tea contains almost 98% water it makes a healthy contribution to the delay
fluid balance. Tea contains no additives or artificial colours. Research indicates
possible antioxidant benefits so drinking tea can be a calorie-free way to increase
intake dietary antioxidants.
Does tea reduces the diuretic effect in comparison to coffee?
The diuretic can be attributed to the caffeine present in tea and coffee. Caffeine
increases diuretic action on the kidneys, increasing urinary volume and sodium extraction
as a result of a decrease in the tubular re-absorption of sodium and water. Coffee
contains a higher content of caffeine compared to tea. Research has shown that a
170ml (6-oz) serving of tea contains, on average 34mg of caffeine in comparison
to 99 mg of caffeine in 170 ml serving of brewed coffee.
As a result the diuretic effect of coffee is greater compared to tea.
Why does tea cloud when it is cooled?
Clouding in tea is a result of the colloidal precipitate that is formed. This is
called ‘tea cream'. Tea creaming takes place when black tea is cooled below 400
C. A weak complexion is formed between caffeine and polyphenols (theaflavins and
thearubigins). The tendency to cream down varies from tea to tea. In black tea without
milk complexation and subsequent precipitation that occurs is negligible due to
just 4% of caffeine.
In tea with milk a similar association takes place between the milk protein casein
and various polyphenols. Due to the availability of casein in milk tea the complexion
is greater resulting in larger precipitation.
Does the water affect the tea brew?
The water used to brew the tea significantly affects the colour and the taste of
a cup of tea. Tea brewed in soft water or permanently hard water (which contains
CaSO4) appears brighter than if it is brewed in temporary hard water (that contains
Calcium bicarbonate CaCO3).
High pH water that contains bicarbonate makes the infusion look darker brown due
to the greater ionisation of the tea polyphenols. While lower pH as in lemon tea
the infusion turns yellow. As for taste some teas are more suited to softer water
such as the orthodox manufactured Assam leaf, while high grown Ceylon and CTC manufactured
teas are better with temporary hard water.
What is tea scum or the dark skin on top of the brewed tea?
It is the result of the high molecular weight components which are formed
due to the influence of calcium and bicarbonate ions at the liquid water interface.
The scum can be removed in two ways
- by filtering the calcium ions,
- by adding acids to covert bicarbonate ions to CO2.
Very little scum is formed on a cup of very strong tea. As the acidic tea polyphenols
themselves partly neutralise the bicarbonate ions. It also should be noted that
less than one mg of scum is formed in a cup of tea and it is not known to be harmful
to human health.
Can overcooked water affect the quality of tea?
Boiling water for too long does dramatically affect the quality of tea. The desirable
brisk taste of tea is created by the interaction of two of its main components,
caffeine and polyphenols. Each component is harsh on its own but as a complex the
compounds moderate each other. Acid levels of water affect the behaviour of these
components.
Water contains minerals and gases absorbed from the earth bed and air. Carbon dioxide
absorbed by air makes the water slightly acidic that influence the colour and taste.
High temperature changes the acidity of water and the acidity is reduced by gradually
driving out carbon-dioxide. Therefore re-boiled water might well brew tea of a different
colour and strength and is unsuitable to brew a good cup of tea.
What is Real Tea?
Tea in its true sense is defined by the International Standards Organisation (ISO)
as, ‘tea derived solely and exclusively, and produced by acceptable processes, notably
withering, leaf maceration, aeration and drying, from the tender shoots of varieties
of the species Camellia Sinensis, known to be suitable for making tea for consumption
as a beverage.
Real Tea is tea produced in the traditional, orthodox manner from the tender shoots
of Camellia Sinensis. The process of manufacture, perfected over centuries is the
most widespread in Sri Lanka with its drying, rolling, fermentation and baking into
the form most people are familiar with – black tea, green tea, white tea. Orthodox
Tea is distinct from the more recent process – CTC (or Cut, Twist and Curl) which
was developed by companies seeking to offer quick colour in a teabag. CTC teas rob
tea of its soul, losing the subtlety of flavour, aroma, variety and character that
Orthodox Teas are prized for. CTC consists of just 3 grades or forms, whilst Orthodox
Tea produces almost infinite variety of leaf size, colour, subtlety of character
and body.
What are Herbal Infusions?
Herbal Infusions, fruit based tisanes and floral infusions are not tea. There are
only three types of tea, black tea, green tea and Oolong tea. In many countries,
notably the USA , these infusions are usurping the health and other benefits of
tea falsely. We give below a brief introduction to the most popular herbal infusions.
CHAMOMILE (Chamomillae romanae)
Chamomile herbal infusions are derived from the plant Chamomillae romanae. It is
a one-year plant, which reaches a height of approx. 55.cm. Chamomile contains 0.6%
- 2.4% essential oils such as angeloyl, methacryl and flavenoids as the main constituents.
The white flower heads are mechanically harvested and dried in chambers to manufacture
the commercial product.
Chamomile was known for its health benefits for centuries and the ancient Egyptians
dedicated it to their sun god, and used Chamomile in their aromatherapy. This legacy
of Chamomile lives on. Studies have that it is beneficial for complaints such as
indigestion, nervousness, depression and headaches.
In testing its Chamomile based product Kamillosan, the Chemiewerke Hamburg Pharmacy
of West Germany found that it reduces gastric acid and helps prevent ulcers. It
also promoted tissue regeneration after patients had operations on their intestinal
tract and urinary system. Chamomile decreases histamine, implicated in ulcers and
the skin swelling, puffy eyes and headaches brought about on by allergies. It is
given to children for digestive and hyperactive problems.
The Greeks named Chamomiles “kamai melon” (ground apple) inspired by its distinct
apple like fragrance and the Spanish called it Manzanilla or “little apple”.
PEPPERMINT (Mentha piperita L.)
Peppermint originated from the Mediterranean but is now cultivated globally in the
Balkans, Northern Europe and the USA . It is characterized by its strong aroma.
It is a perennial herb with a flat root system. It reaches normally a height of
approx. 2-ft and is harvested shortly before blooming. Peppermint contains 0.5 –
4 % essential oil that includes Menthol and menthol esters.
Written evidence of old Egypt indicates that Mentha plants were cultivated and exploited
for medical use 1,000 years before Christian era. It also shows that Mint plants
have represented a valuable object of trade, and was even accepted as tithes to
pay taxes due.
Studies have shown that peppermint tea brings about considerable increase in the
production of bile due to the presence of flavonoids. Peppermint leaf or extracts
prepared from it are included in many (ca. 50) prepared cholagogues and bile-duct
remedies, e.g. Cholagogum Nattermann (capsules, drops), etc. gastrointestinal Remedies
(ca 50), e.g. Gastricholan Iberogast Ventrodigest, etc.), liver remedies (more than
10), hypnotics/sedatives (more than 10), e.g. Nerventee Stada, Esberi-Nervin drops,
etc., and laxatives.
ROSEHIP & HIBISICUS
Usually consists of 70% Hibiscus and 30 % Rosehip. Hibiscus (Hibisci flos) originated
in Angola but is now cultivated throughout the tropics. It is an annual herbaceous
plant with lobed leaves that grows to a height of 5 m. Flowers with a 5-lobed calyx
and divided epicalyx. Hibiscus for infusions is manufactured form the dried calyxes
harvested from the fruit of the species.
It is principally taken as a caffeine-free refreshing drink taken in large amounts
because of the plant acids. The plant acids which are difficult to absorb act as
a mild laxative.
Hibiscus has been extensively used in the African Folk medicine. The drug is ascribed,
among other things, spasmolytic, antibacterial, cholagogic, diuretic and anthelmintic
properties. Studies have shown aqueous extracts of hibiscus flowers relaxes the
muscles of the uterus and to lower the blood pressure.
Rosehip is derived from the plant Rosae pseudofructus. It is a shrub that grows
up to a height of 5 m with thorn branches with flowers close to 5 cm in diameter
with five petals. The drug consists of the dried hypanthia from various species
of the genus Rosa with the fruit enclosed in them. Rosehip is native to Europe,
Western and Central Asia, and North Africa but now it is cultivated in Chile , Bulgaria
, Romania , China and Hungary . It was used in folk medicine as a result of its
diuretic and laxative action due to the pectin and the plant acid content. Due to
its high content of vitamin C Rosehip are used as breakfast teas.
When Tea is not TEA
Green Tea, Oolong tea, Black tea, Decaffeinated Black & Green Tea, the Green
tea component in Jasmine Green tea, and Organic tea are derived from the tea plant,
Camellia Sinensis. Many brands use the word ‘tea' loosely since ‘tea' refers only
to the dried leaves of the plant Camellia Sinensis, and does not include infusions
like Rooibos, Mate, Fruit and other herbal infusions. The term Red Tea, recently
associated with Rooibos, for example refers to the herb from the South Africa shrub
Rooibos (meaning Red Bush).
The traditional forms of tea are White Tea (see below for details), Green Tea (unfermented),
Oolong Tea (partially fermented) and Black Tea (fully fermented). These offers the
health benefits associated with tea whilst others such as Rooibos, Mate, fruit and
other infusions usually do not, although they may have their own specific benefits.
Organic tea
The manufacture of organic tea is carried-out without the addition of Chemical fertiliser,
Pesticides and Insecticides as a result the product doesn't contain chemical residues
which can bring about health effects.
What is White Tea ?
Sri Lanka traditionally produces one of the world's finest white teas in the form
of Silver Tips and Golden Tips, entirely handmade from a special variant of the
Camellia Sinensis plant, untouched by machines and prized for their rarity and subtle
character. The Chinese also have a tradition of producing fine White Teas.
In the production of white tea the 'bud' is selectively plucked and sun dried. Since
the Bud remains undamaged the Catechins or the un-oxidised Polyphenols present remain
intact. What we refer to as Flavonoids in tea, or the antioxidants in tea, include
the un-oxidised Polyphenols or Catechins as in Green Tea and White Tea, as well
as the Theaflavins and low molecular Thearubigins in conventional Black Tea. The
Catechins (Flavonoids) content in the tea becomes progressively less as we go down
from the Bud to the mature leaves in a tea shoot. The bud has the highest catechin
content, next the first leaf, followed by the second leaf and so on.
Hence the sun dried buds or White Tea will have a higher Flavonoid or Antioxidant
property.
Further, since the bud is sun dried (not subjected to high temperature in a drier)
even the vitamin content in the White Tea will remain high and potent. So will be
the Caffeine content. It has been already shown that the bad effects of caffeine
is nullified in Tea by the presence of the Polyphenols in the tea (unlike in coffee
and the colas). Hence the White Tea will have greater nutritive and therapeutic
value than the conventional black tea.
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