Why should we drink Tea?
Tea is second only to water in worldwide beverage consumption. It is taken primarily as a hot drink for its stimulating effects .Drinking tea has many health benefits. It lowers blood pressure, protects the heart, helps to prevent obesity, prevents tooth decay and increases immunity, etc.
Tea contains tannins: are they bad?
The main cause of confusion concerning tea tannins is that they are often mistaken to be associated with tannic acid which is used for tanning leather. However this is false. Tea tannins are polyphenolic compounds that have antioxidant property.
Why are antioxidants present in tea beneficial for us?
Growing evidence indicates that chronic and acute overproduction of reactive oxygen species (ROS) are integral phenomenon in the development of several diseases like heart disease, diabetes, cancer, hypertension etc. Antioxidants present in tea prevent or slow the oxidative damage to our body. Antioxidants present in the tea acts as "ROS scavenger" thereby preventing and repairing the damages done by these free radicals. Antioxidants present in tea enhances immune defense and therefore lower the risk of cancer and infection.
Does Tea increases alertness?
Preliminary research has shown that caffeine in tea is responsible for alertness across the day in the tea drinkers. Studies have revealed that L-theanine in combination with caffeine might be responsible for the positive effect of tea on alertness.
Does Tea disturb sleep?
Anecdotally, many people avoid drinking tea in the evening as they are concerned that caffeine may adversely affect their sleep. Apart from flavonoids tea also contains a unique amino acid, L-theanine. Evidences suggest that L theanine has the ability to promote quality sleep.
Does Tea promote hydration?
There is a common myth that tea acts as a diuretic may therefore might compromise hydration. Scientists believe that if tea is taken regularly, a tolerance to caffeine develops and the diuretic effect is diminished. Moreover tea can provide an important source of fluids and can contribute to the body's hydration levels.
What is the difference between black tea and green tea?
Green tea and black tea are made from the same tea plant, Camellia sinensis. Green tea is made by the leaves being withered, then steamed or pan fried, before being rolled and then dried. It undergoes very minimal oxidation. Green tea contains catechins (catechin, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate) which represent 80–90% and flavonols (kaempferol, quercetin and myricetin glycosides) which is <10% of total flavonoids. The black tea leaf making process involves and additional step of aeration of the cut, withering leaves for several hours. The catechins are turned from the monomer structure to become the dimers that are the theaflavins and the oligomers that are thearubigins The catechin content of black tea is only 20–30%, whilst the theaflavins and thearubigins represent 10 and 50–60% of total flavonoids respectively.
Which type of tea is healthier for you?
Both black and green have different types of polyphenolic compounds. All these polyphenolic compounds have antioxidant property. So both types of tea are beneficial for health.
How do you brew the black tea? And what will happen if water is boiled for too long while making tea?
Water is boiled. 1 teaspoon of tea is placed for each cup into the teapot. Boiling water is poured into the teapot. Tea pot is covered 3-5 minutes according to taste. The longer the steeping time the stronger the tea. Boiling water for too long does affect the quality of tea. The desirable taste of tea is due to interaction of two of its main components, caffeine and polyphenols. Each component is bitter on its own but as a complex the compounds moderate each other. Complex formation leads to the desirable taste often described as “tangy astrigency” This complex contributes to the formation of the coloured precipitation or ‘cream’ when tea liquor is allowed to cool. Normal tap water is slightly acidic because dissolved CO2 gas is present in it. Slightly acidic water enhances the colour and taste of tea. A high temperature changes the acidity of water as carbon-dioxide is driven out during the process. Therefore re-boiled water might well brew tea of a different color and strength and is unsuitable to brew a good cup of tea.
Why theaflavins are considered as important quality parameter for black tea?
Theaflavin, which are thought to be responsible for colours, briskness and taste, and therefore considered to be important for the quality of black tea. Theaflavins contribute to the health benefits of drinking black tea.
Why is Darjeeling tea so special?
Darjeeling tea is widely and universally acknowledged to be the finest tea, because its unique muscatel flavor. Reports suggest aroma molecules including linalool , geraniol, benzyl alcohol , 2-phenyl ethanol , mehyl salicylate, hexanoic acid, (Z)-3-hexenoic acid, (E)-2-hexenoic acid, t-geranic acid, dihydroactinidiolide, N- ethylsuccimide, 2,6-dimethy1-3,7-octadiene-2,6-diol, and 3,7-dimethy1-1,5,7-octatrien-3-o1 etc contributes to the flavor of Darjeeling tea.
What is Organic tea?
The manufacture of organic tea is carried-out without the using chemical fertilizers, Pesticides and insecticides as a result the made tea doesn’t contain any harmful chemical residues which can bring about adverse health effects.
How should we store tea at home?
To preserve freshness of tea it should be stored in a cool and dry place, in a container that is opaque and airtight. An airtight tin is best. Since tea absorbs other odors very easily, it should be stored away from any strong-smelling foods.
What is the average crop loss in tea due to pests?
Estimate suggested that the average annual loss of tea crop in North-East India due to pest, disease and weeds is about 85 million Kg, valued at Rs. 425 crores. The crop loss in tea accounted for anywhere between 6-14% due to the ravages of insect pests.
How these pests are controlled?
Pest control in tea is mainly achieved by the use of synthetic pesticides that have CIB label claim for tea. However, since the 1970, an emphasis on Integrated Pest Management (IPM) practices was given to reduce the pesticide load.
What are the common problems associated with the overuse of chemical pesticides?
Overuse of chemical pesticides can cause secondary pest outbreak together with problems of pesticide residue in made tea. Possibility of development of insect-pest resistance against these insecticides cannot be altogether ignored. In addition to residue problem, other factors such as tainting of tea, toxic hazards to operators and natural enemies of insect-pests can also cause great disturbance.
What amount of pesticide is used in tea in India?
The average use pattern of chemical pesticides was estimated to be 11.5 kg per ha in the Assam valley and Cachar, 16.75 kg per ha in Dooars and Terai and 7.35 kg per ha in Darjeeling (Barbora and Biswas, 1996). In a recent survey, synthetic pesticides constituted 85% of the total pesticides used, while 15% were of organic and inorganic origin in tea gardens of Dooars in which, acaricides accounted for 25% (3.60 litre per ha) and insecticides 60% (8.46 litre per ha). Within the synthetic insecticides, organophosphate compounds (64% - 5 rounds per year) were the most preferred followed by organochlorine (26% - 2 rounds per year) and synthetic pyrethroids (9% - 7 rounds per year).
What are the Pesticide regulations in India with respect to tea?
In India, the concentration of pesticides in food is regulated by two laws (1) the Food Safety and Standards Act, 2006 (erstwhile Prevention of Food Adulteration act 1954) and (2) the Insecticide Act, 1968. The new pesticides molecules are to be registered with CIB&RC before their actual use in agriculture. The Registration Committee of Central Insecticide Board formed under the insecticide act 1968 has the responsibility to check the data requirement of new pesticides and to ensure that pesticide allowed for use will not leave the residues on food commodities above MRLs. It is also liased with international bodies like EPA, FAO, WHO, Codex etc. on pesticide residues. The Government of India, MOC&I vide its order ref. S0486 (E) dated 01.04.2005 has issued the Tea Distribution and Export Control Order, 2005 which will help the country to limit the presence of undesirable substances in tea.
What is MRL?
MRLs are defined as the maximum concentration of pesticide residue (expressed as milligrams of residue per kilogram of food/animal feeding stuff) likely to occur in or on food and feeding stuffs after the use of pesticides according to Good Agricultural Practice (GAP), i.e. when the pesticide has been applied in line with the product label recommendations and in keeping with local environmental and other conditions). MRLs are primarily trading standards, but they also help ensure that residue levels do not pose unacceptable risks for consumers.
How MRL’s are determined?
Once residues are demonstrated to be safe for consumers, MRLs are set based on rigorous evaluation of each pesticide legally authorised. They act as an indicator of the correct use of pesticides, and ensure compliance with legal requirements for low residues on food. MRLs are trading standards used to ensure that imported and exported food is safe to eat. For example, where there is an approved use of the compound on a particular crop, the MRL is generally set at a value determined from field trials (i.e. where the crop has been treated with the pesticide and samples of the crop have been analysed to determine residue levels). MRLs can typically be less than a milligram (mg) of pesticide residue in a kilogram of food (1mg/kg or less than one in a million) up to 5 mg/kg or more.
How many pesticides are currently having label claim from CIB&RC for use in tea?
At present, 35 pesticides have label claim for use in tea as approved by CIB&RC. Among these, there are 23 insecticides, 6 fungicides and 6 herbicides.
What is the purpose of MRL’s?
MRLs are intended primarily as a check that the pesticide is being used correctly (i.e. that the GAP is being observed) and to assist international trade in treated produce.
Is MRL determined for tea or for liquor?
Actually, the MRL is fixed on the commodity on sale. Since black tea is the commodity which is on sale, MRL is fixed on black tea. But it is the liquor, which we drink and not the made tea. It was found that the quantum of pesticide residues that is transferred into liquor is much less than that present in the made tea.
Why MRL’s are different in different countries?
MRL’s are basically based on Toxicological data and GAP. Since, the food habit of different countries vary according to the prefer ability, Fixation of MRL’s of a particular pesticides vary accordingly across the regions of the world.
How MRL’s are fixed in International scenario?
The joint meeting on pesticide residues (JMPR), is an international expert group that consists of the food and agriculture organization (FAO), panel of experts on pesticide residues in food and environment and the world health organization (WHO) core assessment group, has been meeting regularly since 1963. The objective of the JMPR is to recommend MRLs for pesticide residues in food and feed, based on scientific evaluations which are adopted by CODEX through codex committee on pesticide residues (CCPR) for use as international standards by the World Trade Organization (WTO) under the Sanitation and Phytosanitation (SPS) agreement in agricultural commodities moving in international trade. The FAO panel of experts is responsible for reviewing the residue, analytical aspects, metabolism, environmental fate and use pattern of pesticides and for estimating MRLs that might occur as a result of the use of pesticides according to good agricultural practices (GAP). The WHO core assessment group is responsible for reviewing toxicological and related data and for estimating, where possible, acceptable daily intakes (ADIs) for humans of the pesticides.
Is it possible to produce residue free tea?
The tea plantations of India offer congenial environment for a large number of pests, diseases and weeds necessitating judicious use of chemical pesticides. Further, the shorter interval between treatment and plucking of shoots as compared to other crops make it difficult to keep residues low. However, high temperature during tea processing offers scope for degradation of some pesticides. But indiscriminate use of pesticides can invariably leave residues which may render the tea unsuitable for consumption and trade.
