Green Tea vs Black Tea

(What is the difference? How much caffeine in each?)

Although the rest of this website is devoted almost solely to green tea, I wanted to include a page here at the beginning of your explorations into the world of green tea to address what seems to be a fairly common question among people who are more familiar with black tea- namely, what is the difference in black tea vs green tea?

Some familiar forms of black tea are Darjeeling, Assam, and Ceylon. Other general types of tea made from black tea leaves include iced black teas, fruit teas (although sometimes “fruit teas” are not tea AT ALL!), and blended or flavored forms like Earl Grey.  In order to understand the difference between green tea vs black tea we look not at the actual plant that the tea, black or green, comes from because they both are from the same plant, Camellia Sinensis.

The primary difference in green tea vs black tea is in the process the leaves go through after harvest. Black tea is allowed to fully oxidize, or turn brown (as bananas, apples, etc. turn brown as they age or after they are cut or bruised). Green tea, alternatively, is either steamed or pan-fired after harvesting in order to stop the oxidation (turning brown) process so the leaves remain green. This, of course, is a very simplified explanation, and there are other processing factors that differentiate green and black teas.  For the purposes of this discussion, however, we are simply trying to learn about the primary difference between black tea vs green tea, and oxidation is the hallmark difference to understand when comparing the two. Worth mentioning is that oolong tea is somewhere between black and green- having been allowed to oxidize more than green tea but less than black tea.

Another common question among those new to green tea is “does green tea have caffeine”? The short answer is yes. Since both black and green tea are from the same source (Camellia Sinensis plant) they both have caffeine (unless they have been decaffeinated prior to packaging, and even then some caffeine is still present). The caffeine content of green tea does tend to be lower than a serving of black tea, however, due partially to the difference in steeping time and temperatures. Black tea requires a higher temperature (around 190-200F) than green tea (160-180F) and a longer steeping time than green tea. As a result, more caffeine is extracted from the black tea leaves into the drink.

Caffeine content also depends on where the leaves were harvested on the actual tea bush- young leaves near the top of the stems can have higher caffeine than lower, older leaves on the plant.

Surface area of the tea leaves affects caffeine content as well, regardless of whether it is black or green tea. A fine (vs coarse or loose leaf) collection of leaves, like what you find most often in tea bags, has a larger surface area and consequently a higher contact area with the water which increases the amount of caffeine that will end up in your cup.  Of course, the rule of thumb that your cup of black tea will have more caffeine than your average cup of green tea does have a notable exception.  A cup of matcha green tea has more caffeine than some other black or green types of tea due to the fact that with matcha you are actually consuming the tea leaves (which have been ground into powder and stirred into your water) rather than just extracting tea from them as you would when you brew a cup of black or green tea leaves and discard the leaves or bag after steeping.  The truth is, whether black or green tea, the amount of caffeine varies and can overlap.  In general, though, black tea will have a higher caffeine content.

Shown below are caffeine content values for 8 oz of various beverages (measured in milligrams,mg)

Before you decide what you want in terms of caffeine quantity, though, whether you are looking for a quick energy boost or trying to avoid caffeine altogether, be advised that you likely will not have the same experience with caffeine from a cup of tea compared to the same amount of caffeine in a cup of coffee or other caffeinated beverage.  The reason is courtesy of a little amino acid present only in tea: L-theanine. L-theanine actually antagonizes (opposes) the effect of caffeine in tea, and consequently the caffeine in tea may not produce the same nervous, jittery effect that some people experience from the same amount of caffeine in other beverages like coffee or energy drinks.  The caffeine in tea can instead give you more of a slow, steady energy boost.  Also of note, is that green tea has more theanine compared to other tea types– just one more of many reasons to drink your green tea!

So this is pretty much, at least for now, all I am going to say about black tea since this is a website about green tea. I hope you have a better understanding of the basic difference now between black and green tea and that you are ready to dive into the happy world of all things green tea!