What is tea?
“Tea induces lightness of spirit, clarity of mind and freedom from all sense of constriction,
whether mental or physical
and promotes serenity
that mundane cares fall away so that whatever is strident or exacerbating in daily life
can be put out of your mind for a while”
Chinese Tea Emperor- Song Hui Zong
Tea leaves contain 75-80 % water, which is reduced, during the first withering stages to 60-70 percent.
The firing or drying process deactivates the enzyme that causes oxidation and reduces the water content to approx 3-4 %.
During oxidation, polyphenolic flavanols ( or catechins) react with oxygen to create the unique flavor and color of the infused liquor.
The aroma of tea is extremely complex and so far more than 550 chemicals have been identified in the aroma of black tea.
However, the taste mainly results from the various polyphenolic compounds( often incorrectly called tannins) being modified by caffeine.
Both black and green teas contain similar amounts of polyphenols (flavonoids), although quantities vary in different types of tea.
Green tea contains simple flavanoids called catechins while oolong and black teas contain more complex flavanoids called theaflavins and thearubigins.
Tea also contains theanine, an amino acid that occurs rarely in nature and is thought to reduce physical and mental stress and promote a sense of well being and relaxation. It is the magic ingredient that gives tea its famous reputation as the drink that calms you when you are anxious and stimulates you when you are sluggish.
Tea also contains traces of calcium, zinc, potassium, manganese, vitamins B1,B2,B6 and B12, folate, niacin and pantothenate.
Tea & Health
Until the twentieth century, few of the health claims made on behalf of tea had been proven, but recent research around the world and coordinated studies have given us more and more evidence that tea does indeed have many tangible health benefits.
The polyphenols in tea have an antioxidant effect in the body and can help protect against certain age-related and degenerative diseases. These antioxidant effects have been compared to those of certain fruits and vegetables.
In the case of heart disease and stroke, research indicates that tea can help reduce the inflammation connected with atherosclerosis and vascular problems.
Tea polyphenols have also been shown to inhibit the development of cancer cells.
Studies in a number of different countries indicate that tea is also helpful in reducing blood cholesterol, and it is thought that puerh and oolong teas are particularly beneficial.
Tea also aids good dental health as the polyphenolic components in tea have the effect of helping to reduce the formation of bacteria and plaque in the mouth while the fluoride content strengthens tooth enamel. Green tea contains twice as much fluoride as black. In China and Japan toothpaste is now made containing a certain amount of tea extract.
While most scientists have focused on the health benefits of green tea, research shows that black tea may be equally beneficial in disease prevention.
The benefits of tea
are realized when consumed as part of a healthy lifestyle,
on a regular basis over sustained periods of time.
Common knowledge is that tea helps prevent illness than recovery from it.
Summary of the properties of the different teas
Tea & Caffeine
may be one of the most often discussed and least understood
elements in your cup of tea.
Sadly the myths seem more widely accepted than the truths. Even many of the most widely read and respected tea books still promote the old beliefs about caffeine and tea which have long since been proven nothing more than old wives' tales.
While the caffeine in tea and coffee are technically the same, the experience is different due to three key factors:
1)There is significantly less caffeine in the average cup of tea- up to only one third the amount in coffee- especially when including green and white teas brewed at shorter times and lower than boiling temperatures.
2)L- theanine, an amino acid found only in tea, has a relaxing effect that counteracts the jitteriness of caffeine without reducing the increase in alertness.
3)The high levels of antioxidants found in tea slow the body’s absorption of caffeine-resulting in a gentler increase of the chemical in the system and a longer period of alertness with no crash at the end.
A widely cited 2004 British study looked at 200 cups prepared by consumers going about their normal brewing routines. It found that the average caffeine level in the cups of tea was 40 mg. vs 105mg. in the average cup of coffee.
The amount of caffeine in coffee or tea depends on a number of factors, including the length of brewing or steeping.
With tea studies also show that leaf location on the tea plant affects the content of caffeine in the tea.
The youngest leaves, highest on the plant, contain the greatest concentration of caffeine and antioxidants.
Also keep in mind that, because tea bags contain broken leaves of smaller size, they produce an infusion with more caffeine than loose tea does. This is also true of very fine loose tea. In comparison, the same volume of coffee yields at least double the amount of caffeine.
A common myth is that you can “make your own” decaf tea by briefly steeping the tea and throwing away the resulting liquor. The theory is that most of the caffeine is washed away in this initial steeping. The truth, however, is something else entirely. Caffeine is extracted over time, and so the first 30 seconds of a five-minute steeping may only extract 20 to 30 % of the caffeine. As importantly, the antioxidants and other health benefits of tea tend to be extracted more quickly than the caffeine. As a result, that first quick steeping or “washing” removes both the caffeine and the healthy elements found in tea.
To eliminate caffeine intake completely, one must switch to herbal or Rooibos teas which are sometimes referred to as tisanes and do not come from the same family of camellia sinensis.