You are here: Home > All About Tea > Caffeine

ABOUT TEA tea types | c. sinensis | brewing guide | tea & health | caffeine | tea farms | storage | glossary


Caffeine

Caffeine is a compound revered by many and vilified by some. It is a natural substance that occurs in varying amounts in different plant varieties, stages of growth and parts of the plant. It's the magical substance that awakens us and keeps us alert throughout the day. Because of this, people want to quantify and manage its intake.


In moderation, caffeine can be a benefit - stimulating the metabolism, increasing brain function and alertness. However, the stress of modern life, and the prevalence of coffee and caffeinated colas, has lead people to caffeine overload. The typical cup of coffee has approximately 125-185 milligrams of caffeine; the same size serving of tea, about half that amount. Please remember that these are typical levels: depending on how the tea is prepared, caffeine levels can vary greatly. Caffeine is water soluble, so if you lower the water temperature used, less caffeine will be released. For those of you needing a powerful lift in the morning, try matcha- with this type of powdered tea, you consume the leaf itself, not an infusion of the leaf- as it contains significantly more caffeine. Because caffeine from tea does not take effect for 10-15 minutes, it provides more of a subtle lift - not the rapid jolt in a cup of coffee.

The effect of caffeine is also complemented by another compound found only in tea, theophylline. While caffeine primarily is active in the brain and muscles, theophylline is active in stimulating the respiratory system, heart and kidneys. This corresponds to research that tea is helpful in maintaining a healthy cardiovascular system.


Caffeine level can also depend on how the leaf is processed and when it was grown- not to mention the plant variety, and when and how it is picked. For example, some Japanese green teas can have more caffeine than Chinese green teas due nitrogen fertilizer levels, specific cultivars and plant shading. Some white teas have the high level of caffeine because the tea is derived from the new spring growth- buds and young first leaf tips- after a period of plant dormancy. Assamica varietals (Indian teas) can have higher levels of caffeine than most China black teas; some multiple harvest season teas tend to contain 1-5% more caffeine in the spring than in the autumn/winter. These differences can range from 5-30 milligrams per serving, and it is difficult to get precise information from tea producers, who are not in the business of scientifically measuring caffeine levels in their tea. In addition, controlled studies need to be done in order to make accurate comparisons. We must consider that with all the array of factors involved, the variance level of caffeine is still relatively small compared to how much is typically in a cup of coffee.


The Process of Decaf

Two processes are used for decaffeinating tea. One, which makes use of the solvent ethyl acetate, retains only 30% of the polyphenols. The other is a preferable, natural process that uses only water and carbon dioxide and is called effervescence. It retains 95% of the polyphenols. Be sure to check labels to see which process was used. If it isn't specified, you'll have to contact the manufacturer to find out.


Why donít we carry decaf teas?

We find that current decaffeinating methods produce a final product that is bland; the flavor and subtleties are gone. We would prefer those who are affected strongly by caffeine to have an herbal infusion when they feel that they would be adversely affected by caffeine.

We were once influenced by the ever popular adage about removing caffeine from any tea by a quick infusion in hot water. The idea was that because caffeine is water soluble, a quick rinse in boiling water would remove up to 80% of the caffeine.


To adequately address the issue we invite you to read a piece by Nigel Melican, founder of Teacraft and one of the most knowledgeable people on the subject of tea. This was initially published in the CHA DAO blog and parts of it are reprinted here with permission from the author and CHA DAO. We encourage you to follow the discussion on the blog via this link ...