Tea Scapes’ Blog

Just another WordPress.com weblog

Archive for the ‘Black Tea’ Category

Loose Leaf Tea

Posted by Susan Lutfallah on August 9, 2010

Loose Leaf Tea

There are many varieties of tea available today.  English Breakfast, Earl Grey, Green Tea, and Flavoured Tea are all names that we recognize.  The most important thing to remember about all of these teas, is that they all come from the same plant, the camellia sinsensis. The taste difference in the various teas comes from the way in which tea leaves are processed.  The longer the leaves are processed, or oxidized, the darker the tea will be. 

White tea is the least oxidized of all tea varieties.  This gives white tea its very light, sweet, taste.  Green tea is oxidized slightly more than white, and as such will have a deeper colour and offer a stronger more vegetal taste than white tea.  There is much variety even within each kind of tea.   For instance, a green tea may be weak or strong, sweet or pungent, flowery or vegetal, all depending on the method that is used to oxidize the leaf as well as the length of time it was oxidized. 

The hierarchy of light to dark teas looks like this: White, Green, Oolong, Black.  Along with the teas from the  bush, we have also developed other teas from many plants that we have steeped in hot water over the years.  Herbal teas would fit into this category.  Chamomile is a great example of this and is recognized by most as a tea. 

Rooibos is a leaf from an African Red Bush.  It offers a somewhat spicy flavor to many teas and is the base in the most popular chai drink we all enjoy.  Chai simply means tea. 

As you can see, tea comes from many different regions of the world. 

To learn more about TeaScapes, visit us at www.TeaScapes.com

Posted in Black Tea, Green Teas, Matcha Tea, Oolong Tea, Types of Teas, White Tea | Leave a Comment »

Black Tea vs. Green Tea

Posted by Susan Lutfallah on June 6, 2009

Antioxidant Showdown

Until recently, medicinal research regarding tea has focused on green tea – actually, this is understandable, given that green tea is loaded with the compound epigallocatechin gallate (EGCg), a powerful and easily detected anti-oxidant.

Generally speaking, since the fermentation process used to make black tea converts EGCg into other compounds, researchers in the past assumed black tea had less health benefits than green tea.

However, recent studies indicate the compounds contained in black tea – theaflavins and thearubigens – do more than contribute to its dark color and rich flavour – that is, theaflavins and thearubigens also provide health benefits which were originally attributed solely to green tea!

A recent article by Dr. Leung at the Chinese University of Hong Kong reported that drinking black tea has benefits equal to those of drinking green tea in terms of their antioxidant capacities – briefly, this is because theaflavins present in black tea possess at least the same antioxidant potency as catechins present in green tea.

As reported in related studies, it is clear that a group of theaflavins (TF) in black tea, specifically theaflavin-3,3′-digallate (TF3), has strong antioxidant activity similar to (-)-epigallocatechin gallate (EGCG), which is a major antioxidant in green tea.

However, the concentration of diverse antioxidants in the different teas should be first considered before drawing any conclusions about overall health benefits of teas.

In several studies, the total concentration of antioxidants in green tea and black tea were tested – for example, in a study from Cornell University, black and green teas contained total phenols equal to 124 and 165 mg gallic acid (an antioxidant measurement standard), respectively. Moreover, those same researchers found that the antioxidant capacity per serving of green tea (436 mg vitamin C equivalents) was much higher than that of black tea (239 mg).

Therefore, we must conclude that green tea has more health benefits than an equal volume of black tea in terms of antioxidant capacity.

Ok ok, but what about the TASTE?!

Let’s be honest – the recent surge of health food products may help lengthen our lifespan, but they don’t do much in terms of stimulating our taste buds. Put plainly, the taste of green tea for some folks is a major turn off – on the other hand, some don’t mind the taste of green tea initially, but then find the ‘grassy’ aftertaste to be unpleasant.

On the contrary, black tea tasting ‘sweeter’ and it being more pleasantly smelling is commonly accepted, at least in Western culture – conversely, in China and many Eastern countries, the taste of green tea is preferred to black tea. However, black tea is the most consumed type of tea world-wide – therefore, if it is a consumption numbers match-up, black tea wins it.

Posted in Black Tea | Tagged: , , , , , , , , , | Leave a Comment »

Black Tea and Cancer Prevention

Posted by Susan Lutfallah on June 6, 2009

The U.S. Department of Agriculture recently conducted a study which adds to the growing body of evidence that compounds found in both green and black tea have strong anticancer properties on tumours. In fact, the results, which are published in the Journal of the Agricultural and Food Chemistry, suggest that consumers may benefit more by drinking both green and black tea together!

During the study, nine green tea catechins, three black tea theaflavins, and theanine – extracted using either water or a water/ethanol mix – were used on human cancer cells and normal cells.

The majority of the compounds, and all general tea extracts, reduced human breast, colon, liver and prostate cancer cells.

The water/ethanol extracts were found to contain higher levels of flavonoids and kill more cancer cells – because all of the compounds were most effective when used together (a phenomenon known as ‘synergism’), the researchers recommended that consumers drink both green and black teas mixed together!

Moreover, studies done at Rutgers University reveal that black tea may help prevent stomach, prostate, and breast cancer – again, the scientists confirmed that it is the compounds known as thearubigins and theaflavins which may slow down cancer growth. Dr. Kuang Yu Chen and his team at Rutgers argued that some of the cancer cells were undergoing programmed cell death (apoptosis), which seemed to be induced by the thearubigins and theaflavins found in black tea.

Posted in Black Tea | Tagged: , , , , , , , , , , , , , | Leave a Comment »

Black Tea and Aging Diseases

Posted by Susan Lutfallah on June 6, 2009

Recently, a 2008 study conducted at the National Neuroscience Institute in Singapore reported that drinking at least 23 cups of black tea a month may slash the risk of Parkinson’s disease by 71%!

In the study, a staggering number of 63,257 men and women in Singapore were surveyed about their black tea drinking habits when entering the study – over the course of the study, diet and caffeine were ruled out as having no impact on the results. Overall, researchers reported that compounds in black tea other than caffeine appear to be responsible for the beverage’s inverse association with Parkinson’s disease.

A recent study at the University of Newcastle found that green and black tea both inhibit the activity of certain enzymes in the brain which are associated with memory – actually, their findings may lead to the development of a new treatment for Alzheimer’s Disease.

Overall, the scientific researchers investigated the properties of coffee, green tea, and black tea in a series of chemical experiments. After numerous trials, they found that both green and black tea inhibited the activity of enzymes associated with the development of Alzheimer’s Disease – however, coffee had no significant effect.

Intriguingly, both green and black tea inhibited the activity of the enzyme acetylcholinesterase (AChE), which breaks down the neurotransmitter (or chemical messenger) acetylcholine – interestingly, Alzheimer’s is characterised by a drop in acetylcholine. Therefore, by inhibiting AChE, compounds in green and black tea may in turn increase acetylcholine levels; this could be extremely helpful for Alzheimer’s patients.

Furthermore, green tea and black tea also hinder the activity of the enzyme butyrylcholinesterase (BuChE), which has been discovered in protein deposits (known as ‘senile plaques’) found inside the neurons of patients with Alzheimer’s.

While there is no cure for Alzheimer’s disease, it is possible to slow the development of the disease – in fact, there are drugs currently on the market which hinder the activity of AChE, and others are being developed to inhibit the activity of BuChE.

However, many of the drugs currently available, such as donepezil, have unpleasant side effects and the medical community is keen to find alternatives – in fact, researchers at the University of Newcastle hope to formulate a specialized medicinal blend of green and black tea for Alzheimer’s patients!

Posted in Black Tea | Tagged: , , , , , , | Leave a Comment »

Black Tea and Stroke Prevention

Posted by Susan Lutfallah on June 6, 2009

A long-term study by the Netherlands National Institute of Public Health and the Environment found a correlation between regular consumption of black tea and reduced risk of stroke. Researchers concluded that the flavonoids in black tea helped reduce the production of LDL – the “bad” cholesterol that can lead to stroke and heart attacks. Furthermore, men who drank over four cups of black tea per day had a significantly lower risk of stroke than men who drank only two to three cups per day.

Moreover, investigators at UCLA’s School of Medicine sought to identify and summarize all human clinical and observational data on tea in general and stroke – therefore, they conducted a meta-analysis of several scientific experiments to achieve this goal. Although a randomized clinical trial would be necessary to confirm the effect, their meta-analysis suggested that daily consumption of either green or black tea equalling 3 cups per day could prevent the onset of ischemic stroke.

Finally, a separate study by Dr. Joseph Vita at Boston’s School of Medicine supported these results. For four months, sixty-six men drank four cups of either black tea or a placebo daily. Dr. Vita concluded that drinking black tea can help reverse an abnormal functioning of the blood vessels that can contribute to stroke. Furthermore, improvement in the functioning of the blood vessels was visible within two hours of drinking just one cup of black tea!

Posted in Black Tea | Tagged: , , , , , | Leave a Comment »

Black Tea and Tooth Decay

Posted by Susan Lutfallah on June 6, 2009

Drinking black tea may prevent tooth decay – several studies have indicated that the polyphenols found in the refreshing brew can impede or completely suppress tooth decay!

Scientists at the University of Illinois found that the bacteria present in dental plaque simply stopped growing when people rinsed their mouths with black tea!

Briefly, the research found that the polyphenol components of black tea fight dental plaque, a complex material composed of 300 different species of acid-secreting bacteria. Unfortunately, these bacterial plaques can stick to teeth, and can eat away at the protective enamel.

Similarly, a separate study by Swedish scientists also found that people who rinsed their mouths with black tea accumulated significantly less bacterial plaque than a comparable group who rinsed their mouths with only water.

So, if you’re an avid black tea drinker, you can rest easy knowing that your healthy habit is fighting the plaque causing bacteria that can ruin your teeth!

Posted in Black Tea | Tagged: , , , , , , | 1 Comment »

Black Tea, Chronic Stress, and Heart Health

Posted by Susan Lutfallah on June 6, 2009

Drinking black tea has been linked with reduced risk of heart disease in several studies – in fact, a number of these studies suggest that this benefit may be due to lowering of blood levels of low density lipoprotein (LDL) cholesterol (bad cholesterol). Unfortunately, elevated levels of LDL cholesterol are linked with heart disease.

However, the mechanism behind the beneficial effect of black tea in lowering LDL cholesterol levels was unclear – only recently have studies began to demonstrate that it is theaflavins, one of the complex flavonoids in black tea, which is responsible for this LDL-reducing effect.

Recently, researchers at the University College London and Unilever Research Colworth conducted the first randomized clinical trial on the effects of black tea on stress – overall, their results found that drinking black tea may reduce stress hormone levels (cortisol) and ease the burden of heart disease.

During the study, the researchers recruited 75 healthy young males and put them through a four-week “washout” period during which they were not allowed to consume tea, coffee, caffeinated beverages, dietary supplements, and many other substances. Subsequently, 37 of the men were given four cups of black tea per day for six weeks while the 38 members of the placebo group were given an identical-tasting caffeinated drink, with no active tea ingredients, for the same time period.

Afterwards, both groups were asked to perform stressful tasks – these included verbally responding to threats of unemployment and accusations of shoplifting while sitting in front of a camera. During the procedure, the researchers measured the cortisol, blood pressure and blood platelet levels of the subject, and also asked them to self-rate their stress levels.

According to the results, both groups showed significant increases in blood pressure, heart rate and subjective stress levels during the tasks.

However, 50 minutes after the tasks were complete, cortisol levels in the tea-drinking group had dropped by 47 percent compared to only 27 percent in the placebo group!

Additionally, the black tea drinkers showed lower blood platelet activation — which has been linked to blood clotting and subsequent heart attack risk — and a greater degree of relaxation after the tasks.

Posted in Black Tea | Tagged: , , , , , , , | Leave a Comment »

Black Tea and Heart Disease

Posted by Susan Lutfallah on June 6, 2009

Dr Carrie Ruxton, Public Health Nutritionist at Kings College London, conducted several experiments to uncover the health effects of tea consumption. Overall, the researcher thought that the cholesterol lowering effect of black tea could be due to its ability to block cholesterol absorption – that is, reducing the absorption of food-borne cholesterol from the gastrointestinal tract into the blood. Briefly, cholesterol is absorbed from the gastrointestinal tract as part of particles called micelles – therefore, micelles have to be formed for cholesterol to be absorbed.

As a result, Dr Carrie Ruxton tested her idea that black tea might disrupt the formation of micelles – so, her research team mixed together an extract of black tea containing theaflavins together with micelles produced in the laboratory.  Overall, the results confirmed their idea – it was directly observed that the theaflavin containing black tea extract disrupted the incorporation of cholesterol into micelles!

So drinking black tea and increasing the levels of theaflavin in your body can reduce your risk of heart disease by blocking cholesterol absorption – this seems to make sense, since a study of over 3,000 adults in Saudi Arabia – where black tea is favored over green – found that regular consumption of the dark brew can reduce the risk of coronary heart disease by 50%!

Additionally, one study, conducted by the Department of Medicine at the University of Western Australia, found that ingestion of black tea contributed to dilation of the arteries and blood vessels that support the heart (coronary arteries) – this is extremely important, since one of the precursors to heart disease is endothelial dysfunction, a situation where the coronary arteries cannot dilate properly.

Posted in Black Tea | Tagged: , , , , , , | Leave a Comment »

General Health Benefits of Black Tea: Thearubigins and Theaflavins

Posted by Susan Lutfallah on June 6, 2009

Polyphenols are components of the tea plant and the primary source of the health benefits in tea (e.g. antioxidant properties). Polyphenols undergo changes during the processing of the leaves. These changes result in the difference between black and green teas polyphenols and subsequent benefits.

Researchers have determined that the beneficial properties in green teas, primarily EGCG polyphenols, are easier to identify than the flavonoid polyphenols in black teas, which are known as thearubigins and theaflavins.

–          Black teas contain more complex flavonoids then green teas; specifically thearubigins and theaflavins.

–          Thearubigins and theaflavins are powerful antioxidants.

–          Flavonoids, because of their complexity, do not absorb as quickly in the body and initially can be harder to identify (this is why most studies focused on green tea and EGCG polyphenols instead!)

Briefly, scientific reviewers took an in-depth look at epidemiological and clinical studies relevant to tea from 1990 – 2004. Overall, the review’s objective was to determine if consuming black tea has a positive or negative impact on health.

The review concluded;

–          Drinking three cups of black tea per day for two weeks increased the concentration of flavonoids in the blood by about 25%.

–          The consumption of flavonoids can lower the risk of coronary heart disease through a number of mechanisms.

–          Tea flavonoids have also been shown to reduce low-density lipoprotein (LDL) cholesterol by 11.1%.

–          Animal studies and in-vitro (e.g. test-tube experiments) studies both reveal positive effects of flavonoids which go beyond antioxidant capacity – that is, they induce an anti-inflammatory response.

This review of scientific research makes it clear that black tea is good for your health in general, and that black teas complex flavonoid polyohenols specifically can play an important role in daily antioxidant consumption and disease prevention. All-in-all, while green teas continue to steal the health-craze limelight, black tea belong center stage right alongside them!

Posted in Black Tea | Tagged: , , , , , , , , | Leave a Comment »

Black Tea Introduction/History

Posted by Susan Lutfallah on May 6, 2009

Black tea is a variety of tea that is more oxidized than the oolong, green, and white varieties – however, all four varieties are made from leaves of Camellia sinensis. Generally speaking, black tea is stronger in flavour and contains more caffeine than the less oxidized teas. Two principal varieties of the species are used: the small-leaved Chinese variety plant (C. sinensis sinensis), also used for green and white teas, and the large-leaved Assamese plant (C. sinensis assamica), which was traditionally only used for black tea.

In Chinese and Chinese influenced languages, black tea is known as “crimson tea”, which is perhaps a more accurate description of the colour of the liquid. In Chinese, “black tea” is a commonly used classification for post-fermented teas, such as Pu-erh tea. In the West, the expression “black tea” is also used to describe any cup of tea without milk (“served black”), similar to coffee served without milk or cream.

While green tea usually loses its flavour within a year, black tea retains its flavour for several years. For this reason, it has long been an article of trade, and compressed bricks of black tea even served as a form of de facto currency in Mongolia, Tibet, and Siberia into the 19th century.

The tea originally imported to Europe was either green or semi-oxidized. Only in the 19th century did black tea surpass green in popularity.  Although green tea has recently seen a revival due to its purported health benefits, black tea still accounts for over ninety percent of all tea sold in the West.

Assam Black Tea

Assam is a black tea named after the region of its production; that is, Assam, India. Assam tea is manufactured specifically from the plant Camellia sinensis var. assamica (Masters) – in fact, this tea is known for its body, briskness, malty flavour, and strong, bright color.

Assam teas, or blends containing Assam, are often sold as “breakfast” teas – for example, English Breakfast tea, Irish Breakfast tea, and Scottish Breakfast Tea are common generic names.

Posted in Black Tea | Tagged: , , , , , , | Leave a Comment »