Have you ever wonder the normal beverage tea contains around 2,000 chemical compounds!
Yes it is true!
Tea is an aromatic beverage with 2000 chemical compounds. It has cooling, slightly bitter, astringent flavor.
Types of tea
- Black tea (Manufacturing steps: Withering->Rolling->Fermentation->Firing)
- Green tea (Manufacturing steps: Picking->Steaming->Rolling->Drying->Grading)
- Yellow tea
- Red tea
Both green tea and black tea come from the leaves of the plant Camellia sinensis, however the processing that the leaves undergo to make the final tea is different. The leaves for black tea are fully oxidized while those for green teas are lightly steamed before being dried. Black and green teas both contain similar amount of flavonoids, however they differ in their chemical structure.
Green teas contain more of the simple flavonoids called catechins, while the oxidization that the leaves undergo to make black tea converts these simple flavonoids to the more complex varieties called theaflavins and thearubigins.
The chemical structure of tea can be generally divided into
Insoluble part – contains
Soluble part – contains
The soluble part imparts astringency and bitterness (polyphones), sweetness and flavor (amino acids), bitterness and briskness (caffeine) to tea.
Bioactive Compounds in Tea
- Flavonoids
- Caffeine -2.5-5.5%
- Carbohydrates
- Lipids – 7%
- Minerals – 5%
- Volatile compounds – 0.01-0.02%
- Phenolic compounds -25-35%
- Enzymes (Polyphenol oxidases; Shikimate dehydrogenase; Phenylalanine ammonia lyase; Proteinases; Chlorophyllases)
- Flavanols
- Amino acids -1%
It has been consumed for thousands of years and this long safety record makes the compounds produced in the extraction process attractive for drug discovery.
Many research endeavors already claimed that green tea helpful to treat
- Atherosclerosis
- LDL cholesterol – tea inhibit LDL oxidation
- Cancer – Black & Green tea inhibit tumor genesis for cancer
- Cardiovascular diseases
- Inflammatory bowel disease
- Diabetes
- Liver disease
- Weight loss
- Neurodegenerative diseases and
- Halitosis
- Reduced dental cares
- Improves bone mineral density
- Decreases kidney stone formation
Tea is generally considered to be safe, even in large amounts.
However, two cases of hypokalemia (abnormally low serum potassium levels) in the elderly have been attributed to excessive consumption of black and oolong tea (3-14 litre/day). Excessive green tea consumption may decrease the therapeutic effects of the anticoagulant, warfarin (Coumadin).
The health benefits of flavonoids
Although the oxidisation process modifies the type of flavonoids present, the total level and their overall antioxidant activity, is similar in both teas. Research suggests that antioxidants, such as those found in both green and black tea, may have a protective role to play in certain conditions such as heart disease, stroke and some cancers.
Further work is still required in understanding the protective antioxidant action of black and green teas. In one in vitro study, black tea was found to be more efficient than green tea as a chemopreventor against certain free radicals, oxygen and nitrogen species. However, in another study both green tea and black tea were equally able to protect against Nitric Oxide toxicity
Major flavonoids founds in tea
The health benefits of green tea
Green tea has potential anticarcinogenic, antioxidant effects, anti-inflammatory, antithrombotic, cholesterol lowering, antiviral and antibacterial properties. Although the scientific evidence demonstrating the health benefits of green tea is increasing it is not yet conclusive and provides an interesting area for future research
Green tea and skin protection
A number of animal studies have shown that topical treatment or oral consumption of green tea polyphenols prevent UVB-induced inflammatory responses, immunosuppression and oxidative stress, which are the biomarkers of several skin disease states. Treatment of green tea polyphenols to skin has been shown to have a beneficial effect on the biochemical pathways involved in skin inflammation, cell proliferation and chemical tumour promoters. Antioxidant and anti-inflammatory effects of green tea have also been observed in human skin.
Green tea extract and weight loss
Preliminary research published in the American Journal of Clinical Nutrition suggests that an extract from green tea may help with weight loss by speeding up fat oxidation. In this study, researchers conducted a 6 week study of 10 healthy men in their 20’s and found that those men who were given a green tea extract used more calories in a day than those who did not. However, due to the short term duration of the study, the impact of these results on body composition and body weight could not be determined.
Preliminary research published in the American Journal of Clinical Nutrition suggests that an extract from green tea may help with weight loss by speeding up fat oxidation. In this study, researchers conducted a 6 week study of 10 healthy men in their 20’s and found that those men who were given a green tea extract used more calories in a day than those who did not. However, due to the short term duration of the study, the impact of these results on body composition and body weight could not be determined.
Read More: 2000 chemicals in your morning tea
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