Are there certain strains of coffee with higher caffeine content?

Meaning… beans that are grown in Sumatra, for example, will they give you a better kick in the morning than beans that are grown in Kenya?

I don’t believe there really is a lot of difference in the amount of caffeine between different beans.

What makes for higher caffeine in in the preparation. The longer the grounds stay in contact with the water the more caffeine is extracted.

Yes there are indeed beans w/ higher caffeine content.
Here’s a quickie examples. Google’s your friend.

Caffeine Content in beans and blends:

Robusta more than arabica:

The caffeine content of coffee beans varies according to the species of the coffee plant. Beans from Coffee arabica, grown mostly in Central and South America, contain about 1.1% caffeine. Beans from Coffee robusta, grown mostly in Indonesia and Africa, contain about 2.2% caffeine.:

An evaluation of the caffeine content of beans from 99 progenies revealed intra- and inter-progeny variability. In 68 progenies from the Kaffa region we found caffeine values in the range 0.46-2.82% (mean 1.18%), and in 22 progenies from Illubabor region these values ranged from 0.42 to 2.90% (mean 1.10%).


IIRC, roasting reduces caffeine levels also.

Coffee made from Robusta beans will have more caffeine, but not taste as good, (more bitter oils) as a general rule. About 75% of the world’s production is Arabica beans, better tasting beans, less caffeine.

As for Caffeine differences between regions, I think those are going to be very slight, and vary more with growing season, than regions for the same bean. WAG

Plus your roasting, brewing technique, etc. all affects the caffiene delivery system, and it’s efficacy.

And as has already been implied, the greener the bean, the more caffiene! That’s why espresso is really not the ideal drink to get buzzed on. Not enough caffiene in it, mg per oz.

Sorry to bust on you of all people Qadgop, but…
These samples show 13.9 oz of espresso w/ 758mg of caffeine =>54.5mg/oz*

Whereas the 360 oz of brewed coffee held only 3696.5 mg =>10.26mg/oz*

So espresso has at least four times as much caffeine per ounce of beverage as regularly brewed coffee.

Twenty-seven caffeinated and decaffeinated samples were purchased from retail coffee shop s (e.g., Big Bean®,
Starbucks®, Dunkin Donuts®, Royal Farms ®, Einstein Brothers® and Hampden Cafe®) in the Baltimore, Maryland
area; both caffeinated and decaffeinated beverages were included. The caffeine content was determined in the beverages
using liquid/liquid extraction and gas chromatography with nitrogen-phosphorous detection.
Boulenger JP, UhdeTW, Wolff EA, Post RM. Increased sensitivity to caffeine in patients with panic disorder. Archives of General Psychiatry. 1984; 41: 1067 -1071.
Kuczmarski RJ, Carroll MD, Felgal KM, Troiano RP. Varying BMI cutoff points to describe overweight prevalence among US adults: NHANES III (1988-1994).
Obesity Research. 1997;5: 542 -548.
Mandel HG. Update on caffeine consumption, disposition and action. Food & Chemical Toxicology. 2002; 40: 1231 -1234.
TandaG and Goldberg S. Alteration of the behavior effects of nicotine by chronic caffeine exposure. Pharmacology, Biochemistry, & Behavior. 2000; 66: 47 -64.Smith A. Effects of caffeine on human behavior. Food & Chemical Toxicology. 2002; 40 : 1243 -1255. World Health Organization, http://, accessed April 28, 2003.

I left out the decaf number of course.

Other relevant factors are the amount of surface area exposed to the water and the temperature of the water.
Espresso is more finely ground and the water tends to be hotter (~195F) than with drip methods.

Turkish/Arabic coffee (a method preparation) is ground to a powder and ther’re grounds served in the cup. The serving size is (usually) very small- 1oz or so.

I was going to comment on this, but you beat me to it. Perhaps Qadgop meant to say that the darker espresso roast of bean itself has less caffeine than the usually lighter roast used to brew coffee. That is true, but the extraction method, as you pointed out with your citations, pulls out much more caffeine in espresso.

The other possibility is that people often misremember or misquote this stat. One serving (shot) of espresso usually has less caffeine than one serving (cup) of coffee.

My bad. I should have said “per serving” instead of mg/oz. A double espresso is still less caffiene than a regular McDonalds serving of coffee.

Tho in that PDF I do see that caffeine content varies widely from sample to sample.

Even so, ounce for ounce, espresso wins in caffeine concentration. But who the hell will chug an 8 oz espresso? :barfy smile:

Does dark roast coffee have less caffeine than light roast?
It really depends on how you measure the caffeine. If you measure by weight you actually have more caffeine in dark roast because the water loss if faster than the caffeine loss. If you measure by volume you have less caffeine because the beans expand as they roast.

I could easily envision some of your patients doing this. :smiley: