why is it that a cup of coffee has more caffeine content than a cup of tea?

Question

even though tea leaves has greater caffeine content than roasted coffee beans?

Answer 1

Cuban friend is right, but there's one more thing that is particularly pertinent: caffeine is very water-soluble. The longer water has contact with the source, the more caffeine is pulled out of the source and into the water. This mostly explains the difference in differing levels of caffeine in teas, but I think w/espresso, because the water is forced through the beans at high pressure, more of the caffeine and content of the ground up beans gets forced into the liquid.

Answer 2

Tea and Coffee come from different plants and as such the two plants produce different alkaloids in different quantities( If they produced the same alkaloids then they would be the same plant). Caffeine is produced in greater amounts in the Coffee Tree than in the Tea Bush. When Coffee is roasted some of the Caffeine is lost, but it still has more than tea! Tea is (usually) not roasted but instead is smoked to a dry state. Unsmoked teas (green) have even milder flavors. Coffee is picked when it is Ripened and after it berries concentrate ingredients whereas tea is picked when it is green and caffeine is less concentrated
All of these factors contribute to why Coffee has more caffeine than tea does!

Answer 3

Depending on the tea (white/green/black) caffeine content varies from around 30-50mg in an 8 oz cup. Espresso coffee has around 75-100mg in a 2 oz double shot. Brewed coffee (from Arabica beans) can range from 120-180mg in an 8 oz cup. Robusta coffee has about 2x the caffeine of Arabica & a very bitter taste. Instant coffee (not real coffee IMO) has around 80mg of caffeine. So by volume (8oz): Espresso wins with up to 400mg of caffeine in one cup, then brewed, then instant, then tea. Sodas average less caffeine than tea, although they have 0 health benefits.

Answer 4

All figures are approximate, especially with coffee. Different varietals can have different caffeine content, and the way the coffee is roasted can also change the values.

Double espresso (2oz) 45-100 mg
Brewed coffee (8 oz) 60-120 mg
Instant coffee (8 oz) 70 mg
Decaf coffee (8 oz) 1-5 mg
Tea - black (8 oz) 45 mg
Tea - green (8 oz) 20 mg
Tea - white (8 oz) 15 mg
Coca Cola (12 oz can) 34 mg
Pepsi (12 oz can) 38 mg
Barq's Root Beer (12 oz can) 22 mg
7-up (12 oz) 0 mg
Chocolate milk (8 oz) 4 mg
Dark chocolate (1 oz) 20 mg
Milk chocolate (1 oz) 6 mg
Ben & Jerry's Coffee Fudge Frozen Yogurt (8 oz) 85 mg

Answer 5

tea is not made very strong, while coffee usually only has two modes, strong and super strong. also more coffee beans are used to make a cup of coffee while there aren't many tea leaves used to make a cup of tea.