In this episode of “Brewerteapedia” we are looking at the question if and how much caffeine is there in a cup of tea? The answer is yes, while drinking tea you will get caffeine in your body. Although it’s effects is much slower then when you drink a cup of coffee.
Caffeine occurs naturally in the leaves of tea. The amount varies according to the oxidation process and brewing methods and time. Herbal and rooibos tea doesn’t contain caffeine due to the fact that they are not made from the plant that produces tea.
Tea belongs to a very small group of botanicals which have the unique ability to produce caffeine during the photosynthetic process. In tea, caffeine-production occurs exclusive in the leaves, not the roots or stems. Sugar, which is the normal by by-product of all plant photosynthesis, becomes caffeine in the tea plant.
Can you get addicted to caffeine?
Caffeine is the most popular drug in the United States and the least regulated one. Caffeine is the only drug that is present naturally. Other natural caffeine producers are found in coffee, chocolate and yerba mate. But it is also added to widely consumed foods, like cola and chewing gum. It is mildly addictive, one possible reason that makers of soft drinks add it to their products. Many coffee drinkers experience withdrawal symptoms, such as headaches, irritability, sleepiness, and lethargy, when they stop drinking coffee.
Tea contains much more of it by weight than coffee, but far less tea is used to brew one serving of tea. The effect of caffeine on the body from drinking tea comes on far more slowly than the effect from drinking coffee. So when you hear “relax with a cup of tea,” it’s because drinking tea seems smoother and mellower than drinking coffee.
How much caffeine is there in tea?
Many factors influence how much caffeine is present in plucked tea leaves. These include the growing region, plant varietal, plant age, leaf age, length of the growing season, field conditions, soil nutrients, rainfall, and stress by pests. Final caffeine content may be further affected during production of the leaves into the finished “style” (white, green, etc.).
How the tea is actually prepared plays an important role in how much caffeine makes it into your cup. Everything, from the amount of tea used to water temperature and brewing time to whether the leaves are steeped loose, in a tea bag, or strainer, becomes a factor. In general, though, more tea, hotter water, and longer steeping all contribute to more caffeine per cup. 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.
Given all of these variables, it really is difficult to answer the question, “How much caffeine is in this tea?”. Please keep in mind that these numbers reflect varying steeping times and amounts of tea leaves per cup.
Caffeine content in an average cup:
|Beverage (8 oz. / 237 ml.)||Caffeine (mg)|
|Black, decaf tea||2 - 5|
|White tea||10 - 15|
|Green tea||25 - 29|
|Oolong tea||27 - 35|
|Yellow tea||35 - 38|
|Black tea||25 - 48|
|Yerba Mate tea||85 - 88|
So, caffeine levels tend to vary based on leaf size, brewing time and water temperature. The larger the leaf, the longer the brewing time and the hotter the water temperature, the more caffeine releases into the brew. In herbal and Rooibos tea, no caffeine is present, since it’s origin is not official considered tea.
How much caffeine is in a cup of decaf tea?
Decaf tea has been processed to remove the caffeine. There are various methods to do this. It is unlikely that all the caffeine is 100% removed in decaf. But the quantity that remains is so low that producers can claim that it’s caffeine free. If you really don’t want any caffeine, drink a tisane instead, for example when you are pregnant of breastfeeding.
On a commercial level, the removal of caffeine from tea is generally done by one of three available methods:
In solvent based extraction, ethyl acetate is used to “capture” the caffeine from the leaf. The solvents are then removed by filtration carrying with them the caffeine. This method is widely used, but using chemical solvents carries the risk that some solvent remains on the leaf, albeit in very small quantities.
the tea leaves are wetted first to break up intercellular plant tissue. Then the tea is put into a kind of pressure chamber in which pressurized CO2 streams through the tea, taking with it the caffeine, but leaving behind other flavor components. The extracted caffeine is then filtered out of the CO2.
The leaves are introduced into a steam chamber, which removes much of the caffeine, although this method has a lower efficacy than the other two methods
A Thought About Serving Sizes
Caffeine levels are often reported in terms of mg per 8 oz cup, but people seldom drink only 8 oz of tea or coffee. Trying to relate reported caffeine to actual personal consumption doesn’t always give an accurate comparison. Why? Consider this:
If an 8 oz cup of brewed coffee contains 150 mg of caffeine, a 16 oz cup of coffee will have 300 mg.
Similarly, when you drink an 8 oz cup of tea served from a brewed pot of tea, doubling the serving size to 16 oz results in double the caffeine.
But steeping tea in a mug is different.
If you were to brew a mug of tea using 8 oz of water and one tea bag, the total caffeine could be around 40 mg. If you were to brew a larger mug of tea using 16 oz water and one tea bag, the total caffeine would not double. It would still be only around 40 mg!
The effects of caffeine in Tea vs Coffee
Originally called “theine”, caffeine was first discovered in tea in 1827. It was later shown that the “theine” of tea was identical with the caffeine of coffee. The term “theine” was then dropped. While the caffeine in tea and coffee are, technically, identical, the experience is different due to three key factors:
1. There is significantly less caffeine in the average cup of tea – especially when including green and white teas brewed at shorter times and cooler temperatures.
2.The high levels of antioxidants found in tea slow the absorption of caffeine – this results in a gentler increase of the chemical in the system and a longer period of alertness with no crash at the end.
3. L-theanine, an amino acid found only in tea, reduces stress and promotes relaxation. It works with caffeine in a synergistic way to calm the body without reducing caffeine alertness.
When is daily caffeine intake too much?
You may want to take a look at just how much caffeine you get in a typical day. Especially if you’re bothered by headaches, restlessness or anxiety. If your caffeine habit totals more than 400 milligrams (mg) a day, you may want to consider cutting back. So that is on a daily basis when you are drinking more then 10 cups of black tea if you only drink tea.
Reading this article might have convinced you that the caffeine level in tea is not alarmingly high. And that herbal tea might actually be a good alternative if you want to lower your caffeine intake.
But exactly how much caffeine is there in the other food and beverages you consume on a daily basis? Use this table to calculate your intake. This article is good to read if you are interested in the effects of caffeine on the body
How much caffeine is there in other beverages?
|Beverage||Serving size (oz./ml.)||Caffeine (mg)|
|Starbucks Coffee Blonde Roast||Venti, 20 oz. / 590 ml.||475|
|Starbucks Coffee Pike Place Roast||Grande, 16 oz. / 470 ml.||310|
|Starbucks Coffee Pike Place Roast||Tall, 12 oz. / 355 ml.||235|
|Dunkin' Donuts Cappuccino||Large, 20 oz. / 590 ml.||233|
|Starbucks Caffè Americano||Grande, 16 oz. / 470 ml.||225|
|Starbucks Caffè Mocha||Grande, 16 oz. / 470 ml.||175|
|Monster Energy||Can 16 oz. / 470 ml.||160|
|Nespresso Kazaar capsule||1 capsule, makes 1 oz.||120|
|Pepsi Zero Sugar||20 oz. / 590 ml.||115|
|Starbucks Mocha Frappuccino||Grande, 16 oz. / 470 ml.||110|
|Brewed coffee||8 oz. / 237 ml.||95|
|Starbucks Chai Latte Tea (iced or regular)||Grande, 16 oz. / 470 ml.||95|
|KeVita Master Brew Kombucha||15 oz. / 444 ml.||80|
|Red Bull||8 oz. / 237 ml.||65|
|Diet Coke||20 oz. / 590 ml.||76|
|Espresso coffee||8 oz. / 237 ml.||65|
|Instant coffee||8 oz. / 237 ml.||63|
|Mountain Dew—diet or regular||12 oz. / 355 ml.||54|
|Black tea||8 oz. / 237 ml.||40|
|Arizona Iced Tea, black||Can 16 oz. / 470 ml.||30|
|Arizona Iced Tea, green||Can 16 oz. / 470 ml.||15|