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.
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.
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."
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 role 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 Dilmah 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.
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.
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
Chamomile herbal infusions are derived from the plant Matricaria recutita. 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 flavanoids 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”.
Usually consists of 30% Hibiscus and 70 % 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.
Where should you store your tea?
In a cool and dry place, in an air tight container made out of suitable barrier material, away from light sources and heat, preferably in a refrigerator.
Avoiding a few undesirable factors by considering appropriate storage conditions will make a difference in the shelf life of your tea. The factors to be avoided are direct light sources including direct sun light, heat, moisture, odour and exposure to air.
Why should you store tea in a cool & dry place, in an air tight container, away from light sources and heat?
Tea being a hygroscopic substance, readily absorbs water from its surroundings. Tea quality deterioration on storage was found to accelerate with high relative humidity and heat and it is for this reason that storage in cool and dry conditions is essential.
Water activity which is a measure of the free moisture in a product is one of the most critical factors responsible for the quality of tea. The water activity affects the shelf life, product quality and safety including texture, flavor & smell. The water activity may be the most influential factor for controlling tea degradation. Effect of temperature on water activity of a food is product specific. Water activity of tea has a tendency to increase with temperature. Therefore, it is required to store tea under low temperature to avoid the effect of high temperature on water activity. Ideal temperature is below 25°C and the recommended maximum temperature is 30°C
According to the typical sorption and desorption isotherm of food, the water activity increases with the moisture content. Therefore, the relative humidity should be maintained at a lower value to prevent the increase of tea moisture. Ideal relative humidity is below 55% and the recommended maximum relative humidity is 70%
Tea when exposed to air increases the chances of absorbing moisture and strong odour. Materials with low barrier properties such as paper bags if used during storage may also contribute to absorb moisture to tea through the packaging material. That is why it is essential to store tea in an air tight container made of suitable barrier material.
Quality deterioration of tea stored even in air tight containers may sometimes be unavoidable if the tea is exposed to light sources, especially UV or IR radiation. Sun light degrades your tea. Excessive heat too degrades your tea very fast. That is why it is important to store your tea away from direct sun light and heat.
Does teabag filter paper contain Bisphenol A?
Bisphenol A (BPA) is not a raw material used in the process of production of filter papers and is not known or expected to be present in the raw material used in the production of filter papers.
Does teabag filter paper contain Epichlorohydrin?
There have been a number of statements on selected websites that use of teabags filter papers can have health effects as they are made with, or coated with, epichlorohydrin which is considered to be a potential carcinogen. The statements are at best ill-informed and misleading and the statement that epichlorohydrin is used to coat the paper is incorrect.
The filter paper materials used are fully compliant with relevant legal requirements and good practice guidelines for papers which are in direct contact with food such as those detailed below:
Regulation (EC) No 1935/2004 of the European Parliament and the council
American FDA regulations 21 CFR Ch. I §176.170+176.180
German Foodstuffs, Consumer and Animal Feed Code(LFGB) §30+31
Biodegradable/ compostable material?
Biodegradable material can be composted. The rate of degradation of any material is dependent on the type of material and the conditions involved in the process such as moisture, heat, PH level and type/ number of microorganisms present. This clearly indicates that the compostable nature depends on the type of material as well as on the methodology applied – example: Backyard Composting or Industrial Composting
How can we evaluate the biodegradability of material?
As per the EN 13432: 2000, there are laboratory tests to check the biodegradability of the materials. Example: The controlled aerobic composting test.
Is filter material compostable?
All filter materials are compostable materials. However the rate of degradation is dependent on the type of filter material used, the conditions and methodology applied for composting. The woven filter material used for the production of the pyramid triangle bag is compostable in industrial facilities and not suitable for backyard composting. The filter material used to produce the double chamber crimped sealed bag is a fully biodegradable material produced using natural cellulosic fibers.