Caffeine is naturally occurring in the tea plant, known as Camellia sinensis, and will be found across all tea categories: white, green, oolong, black & fermented. Caffeine and its associated compounds are used as the tea plant's powerful and natural defense against insects.
Before brewing, dry tea leaves actually contain about the same amount of caffeine as coffee beans by weight. However, after steeping your tea leaves in hot water, tea has less caffeine than coffee - usually about 1/3 to 1/2 the amount found in drip coffee. There is typically somewhere between 25-50 mg of caffeine in one 8 ounce cup of tea.
Of course, there will be exceptions, such as matcha, which can have as much or more caffeine than a cup of coffee. Matcha is a finely ground powder made from green tea leaves. When you drink a cup of matcha, you are consuming the ground leaves vs. steeping the leaves in water. With matcha (and with tea in general) due to the high content of L-theanine, which slows caffeine absorption, many people may experience a kind of calm alertness instead of the jitteriness that often accompanies coffee or other caffeinated beverages. Caffeine will affect everyone’s metabolism differently.
Here are some factors that will affect the amount of caffeine in your cup of tea:
- age of plant
- type of plant
- age of leaf
- elevation or area where plant is grown
- water temp
- time in water
- tea to water ratio
While it can be difficult to pin down details on the age and elevation of the plants your tea leaves came from, one major factor that affects the amount of caffeine in your tea is how you prepare it. Green and white teas are typically prepared using cooler water and are only steeped for 3 minutes, compared to black teas which are steeped for 5 minutes using water just off the boil. Therefore, black teas will typically have higher levels of caffeine, as more caffeine is extracted from the leaves. Hotter water, longer steep times and increased leaf to water ratio will augment the amount of caffeine in the cup. According to some of the most recent research on caffeine in tea, it takes 15 minutes of steeping in boiling water to fully extract 100% of the caffeine from your tea leaves.
If you are looking to avoid caffeine all together, rest assured there are still some highly enjoyable options. At Smith, all our herbal infusions are caffeine free.
We currently do not source any decaffeinated teas. The decaffeination processes for tea indeed removes much of the caffeine as well as other chemical compounds from tea, resulting in a less than desirable flavor and unimpressive cup of tea.