Tea, known by its botanical name Camellia sinensis, is the second most popular beverage consumed in the world — second only to water! It’s estimated that every year around 2.5 million tonnes of tea leaves are produced and enjoyed by tea lovers the world over. The story of tea encompasses many varieties, all made from this one plant, and the many health effects that arise from this singular brew.
Tea varieties
All varieties of tea we discuss here — white, green and black — come from the same plant, Camellia sinensis. To make the different varieties of tea, the fresh tea leaves undergo different levels of oxidisation: a natural chemical reaction that produces a variety of different tastes and colour characteristics.
Tea plants need to be immaculately maintained and cultivated, as the quality of tea is highly dependent on a number of factors, including the colour of the leaves, their nitrogen content and the extent of damage done to the leaves. Careful harvesting — either by hand or finely tuned machines — selectively removes only the uppermost two or three leaves from any tea plant.
White tea
White tea leaves are harvested at a younger age than green tea leaves. Harvesting occurs just before the tea leaf fully opens, while it’s still a bud and covered in white, silvery, fine hairs. White tea is considered a rare and precious tea and is usually more expensive than other teas. It can only be hand-picked over a few days in early spring and has to be handled with extreme care.
Unlike black and green teas, white tea isn’t rolled or steamed but simply air-dried in natural sunlight, making it the least processed of all the teas. This preserves more of its antioxidant properties, about three times as many antioxidant polyphenols as found in green tea, and it contains the least amount of caffeine.
There are four main varieties of white tea: Silver Needle (made just from silvery white buds), White Peony (buds and leaves), Long Life Eyebrow (leaves) and Tribute Eyebrow (made with a special tea bush, which is processed slightly differently).
Green tea
Green tea undergoes only a minimal amount of processing. The freshly harvested leaves are immediately steamed or pan-fried to prevent oxidisation. The leaves are then rolled; a process which ruptures the cells of the leaf to enhance brewing and make drying easier. Thus the rolled leaves are then dried.
The processing methods used to make green tea help preserve the leaves’ natural antioxidant polyphenol levels and health-promoting properties. They are also responsible for green tea’s subtle taste, grassy aroma and, importantly, its resultant green colour.
Green tea is the perfect beverage to assist with meditating, as it is mildly stimulating with its moderate caffeine content yet it helps to keep you calm and focused due to its L-theanine levels.
There are many different varieties of green tea available, created through varying growing conditions, processing methods and harvesting times. Some of the most popular varieties include Japanese sencha, a roasted green tea that’s the most popular tea in Japan; gyokura, an expensive fine tea; bancha, a lower-grade tea made from the twigs of the tea plant; genmaicha, made with roasted brown rice; matcha, a powdered green tea; and jasmine tea, a well-known Chinese tea scented with jasmine blossoms.
Matcha tea is a powdered green tea enjoyed by Japanese people since 1141 AD. This healthy drink is the main focus of tea ceremonies dating back to Ancient times. Matcha is made from high-quality, whole tea leaves that are finely ground into a powder. To prepare a bowl of matcha, a teaspoon of powder is added to one-third of a cup of hot water, then whisked with a bamboo brush until it becomes frothy. Matcha has a distinct grassy taste and can also be made into a latte with milk and sweeteners. Because the whole leaves are consumed by the drinker, much higher levels of powerful antioxidants called polyphenols, namely epigallocatechin-3-gallate (EGCG) are also consumed compared to regular green tea.
Green tea has become an increasingly popular addition to health foods and beverages, nutritional supplements and even cosmetics.
Black tea
Black tea undergoes the most processing and oxidation of all the teas, giving it its distinctive aroma, taste and dark colour. Black tea is also called Qi Hong or Red Tea by the Chinese.
There are four basic stages involved in producing black tea: withering, which softens the leaves to reduce moisture; rolling, which breaks the leaf cells and starts the oxidation process; oxidation, when the tea starts to develop its unique aroma, colour and taste; and drying.
As green tea is fermented to oolong and then to black tea, polyphenol compounds (catechins) in green tea are dimerised to form a variety of theaflavins, such that these teas may have different biological activities.
This longer oxidation process changes catechins in green tea into a variety of theaflavins that are unique to black tea. These polyphenols aren’t as potent as catechins, however they still provide health benefits.
There are two different methods used to process black tea. First, “orthodox” methods yield loose-leaf, artisan teas and, second, “cut-tear-curl” techniques produce broken-leafs, fannings (finer broken particles) and dust (fine powder), used for teabags.
The cut-tear-curl method is often thought of as being inferior in quality and flavour, while whole leaves are commonly viewed as most desirable.
Caffeine comparison
Caffeine content varies depending on the type of tea. White tea has around 15mg of caffeine per cup, green tea around 20mg and black tea 45mg. This is much lower compared to a brewed coffee, which has 100–300mg of caffeine per cup.
For those who are sensitive to caffeine, decaffeinated teas are now commonly available. Or you can simply steep your tea twice. Most of the caffeine from tea can be removed by pouring hot water over the leaves and then leaving it for 30 seconds. Caffeine in tea is released during the first 30 seconds of steeping. Pour out the tea and then re-steep tea with more hot water using the same leaves.
Matcha tea contains more caffeine than green tea and is similar in caffeine quantity to a cup of coffee. However, when drinking matcha, it gives an energy boost without the nervous jitters that can sometimes come with drinking coffee. This is due to matcha being a great source of L-theanine, an amino acid that creates alertness along with a sense of calmness, encouraging clarity and improved concentration.
How to make the perfect cup
To make the perfect cup of tea, you should generally use one heaped teaspoon of tea per cup of water.
Different teas have different brewing times and preferred temperatures.
White and green teas should be brewed at around 70°C, and black around 85°C. Steeping tea for too long or using boiling water will result in more tannins being released, leading to a bitter and more astringent tea. The amino acids responsible for tea’s flavour are released at lower temperatures.
There are two simple ways to make sure water is not too hot to lessen the quality of tea: either the kettle can be stopped just before boiling, or pour boiling water into the tea cup or pot and allow it to cool a little before adding the tea.
White tea should be steeped for 1–3 minutes, green for 1–2 minutes and black tea either 45–60 seconds (without milk) or, for a stronger, richer tea served with milk, 2–3 minutes.
Good-quality teas can be reused. They can be infused two to three times, which will bring out different flavours and subtleties in each brew. The Chinese believe the second or third brew of good-quality tea is often the best.
Health benefits
Over the past few decades, green tea has been subjected to numerous scientific studies to establish the extent of its long-purported health benefits. Scientists believe green tea’s health benefits are due to its polyphenols, which are natural plant compounds found in high levels in green and white tea that act as potent antioxidants. These chemicals neutralise free radicals that are associated with the development of chronic diseases such as cardiovascular disease and cancer.
There are numerous polyphenols found in tea, including catechins (epigallocatechin gallate (EGCG), epigallocatechin, epicatechin gallate, epicatechin), theaflavins, tannins and flavonoids. Catechins make up a majority of the pholyphenols found in green tea, with the most active and most extensively studied being EGCG, which is unique to white and green tea and is also available as a green tea extract added to nutritional supplements.
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Tea also contains alkaloids, including caffeine, theobromine and theophylline, which provide tea’s stimulant effects, and L-theanine, an amino acid compound found in green and white tea that has been studied for its calming effects on the nervous system.
Since white and green teas are treated gently and are not over-processed, they retain most of their beneficial antioxidants. White tea contains the same types of antioxidants as green tea, but in greater quantity. These antioxidants have been found to have many health-promoting properties.
Cardiovascular health
Research shows that antioxidants found in green tea may help lower cholesterol levels and help protect against coronary heart disease and stroke. According to a Japanese study published in the JAMA, women who drank five or more cups of tea a day had a 31 per cent reduced risk of dying from cardiovascular disease, and a 42 per cent lower risk of stroke.
Cancer protection
Clinical studies have also linked green tea consumption to the prevention of a number of different types of cancer, including breast, colon, lung and stomach.
Weight loss
Drinking green tea has also been shown to help encourage weight loss by increasing metabolism and fat burning. According to the International Journal of Obesity (2000), green tea’s thermogenic effect is due to the synergistic effect of its caffeine content and catechins, which boosts metabolism.
Tea catechins, especially EGCG, seem to have an antidiabetic and antiobesity action.
Liver function
Green tea has also been found to have a positive effect on liver health and may offer protection against liver disease.
Oral health
Green tea consumption is also associated with better oral health. Researchers discovered that polyphenols found in green tea can help protect against bacterial-induced dental caries, bad breath and oral cancer.
Bone density
Drinking green tea may also help improve bone health by increasing bone mineral density.
Organic is better
A 2014 Greenpeace report revealed the presence of a variety of pesticides found in teas grown and sold in India. These teas are also exported around the world by major tea companies. The WHO (World Health Organization) has classified a large percentage of these pesticides as moderately or highly hazardous, and some levels being above the recommended safe limits.
This is very concerning considering India supplies over 11 per cent of the world’s tea exports, to countries including the US, UK, Germany and Russia. Of all the tea samples taken, 34 different pesticides were found, with 23 of them being unregistered for use in tea cultivation in India. Nearly all samples contained at least one pesticide, and more than half contained more than 10 different pesticides. Alarmingly, the long-banned compound DDT was also detected in some samples.
These findings were similar to Greenpeace investigations in 2012 revealing high levels of pesticides in Chinese tea, published in its report Pesticides: Hidden Ingredients in Chinese Tea. China is the largest producer of tea in the world and the biggest user of pesticides. Of all the 18 samples taken from nine popular Chinese tea brands, 29 different pesticides were detected. All of them were found to have at least three different types of pesticides, 12 of them had traces of banned pesticides — that have been associated with infertility and birth defects — and six of the samples contained more than 10 different kinds of pesticides.
Excessive pesticide use greatly damages the tea plantation environment with a large percentage of these toxic pesticides ending up polluting the air, soil and water. The health of the tea workers is also put at risk as they are coming in contact with these dangerous chemicals on a regular basis. Moreover, end-users or tea drinkers are thus, unknowingly, ingesting traces of these damaging chemicals in their daily cup of tea.
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Organic tea farmers work in harmony with nature, using environmentally friendly, chemical-free techniques to grow and process their teas. Instead of using harmful chemicals, organic farmers use natural and traditional methods of weed and pest control, which help preserve the quality of the soil and nearby waterways, and surrounding ecosystem, to produce clean, healthy, chemical-free tea. Consumption of organic tea must, by most measures, therefore be regarded as much better for the tea-drinker’s health, the safety of tea plantation workers and the environment.
When purchasing organic tea, look for the “certified organic” logo such as the certified organic bud to ensure the organic integrity of the tea product. ACO is the most well respected, strictest and most thorough food regulatory program here in Australia and internationally.
If more people choose to buy organic tea, more farmers will be encouraged to grow it, which means fewer toxic chemicals on and in tea leaves and less harm to the Earth.
