Most of the green tea sold comes from the camellia sinensis sinensis variety originating from China.
The big difference between green tea and black tea is the point in which the tea leaves are harvested.
The leaves of most green tea are quickly harvested and processed before oxidation can start. Oxidation is a chemical process where the tea leaves are exposed to the air ( oxygen), causing them to dry out and change color and brown, think of what happens to an apple after yo u take a bite, it starts to turn brown! the same 'reaction" is happening to the delicate tea leaves.
The process of oxidation in tea leaves changes the flavor of tea and makes the flavor profile bolder and richer.
Green tea I roasted at a lower temperature and a shorter time period than black tea.
Black Tea
Black tea is prepared from growing the camellia sinensis assamica variety originating from India. Black tea is a much darker color of tea, this color is created by fully oxidizing the tea leaves before they are dried and prepared for sale.
Black tea has a deeper bolder flavor profile, and may be slightly astringent due to its higher tannin content.
Now lets compare them!
When brewed Green Tea in a 1/2 cup servings, it contains 133 milligrams of flavonoids.
A 1/2 cup serving of Black Tea contains 119 milligrams of flavonoids. This difference is due to the oxidation process that black tea leaves undergo, because the browning of the leaves causes some loss of total flavonoids.
Green tea has more of these antioxidants called epigallocatechin-3-gallate (EGCG).
ONLY black tea contains theaflavins, they will not be found it in any other tea.
Theaflavins have been shown aid our bodies in producing our own antioxidants. They have also showed promise in reduce cholesterol and blood sugar levels.
They also help break our bodies breakdown fat, protect the stored fat cells from free radical damage( this also helps prevent cancerous cells from developing and/or spreading).
Green tea has the lowest of the tannin contents
Black tea has the highest concentration of tannins of all the tea types.
Caffiene content in 1cup :
green tea : 25-40 milligrams of caffeine
black tea: 40-60 milligrams of caffeine( depending on variety)