Caffeine content of roasted beans.

[Skeltron]

I hope this is something everybody knows. I don't mind looking dumb if it means that I can get a quick answer to my question.

Does anyone know the quantity of caffeine per ounce of fresh roasted Arabica beans? I'm interested in dark roasts especially.

I've rummaged around the net and found plenty of comparisons of coffee, tea, chocolate and the like -- but these invariably refer to the caffeine per cup of brewed coffee (presumably one of the lighter roasts at a realatively low concentration). I have found generalities stating that the roasting process actually destroys caffeine, so that green beans have lots more than roasted beans and light roasts have more than dark roasts. But nobody seems to want to let go of quantitative information like, "How many milligrams of caffeine in an ounce of French roast beans?" Can anyone help?

 

[FPDoc78]

I believe medium roasts are around 200. Therefore darker roasts must be slightly less. To put it in perspective a can of coke has around 50 if my memory serves me.

 

[coffeeroastersclub6]

I hope this is something everybody knows. I don't mind looking dumb if it means that I can get a quick answer to my question.
...snip...But nobody seems to want to let go of quantitative information like, "How many milligrams of caffeine in an ounce of French roast beans?" Can anyone help?

Hello. Just a note on roasting. The more you roast a bean the more caffeine you lose. Keep that in mind when you do your roasts.

Len

 

[3ternal]

I'm pretty sure this wont help, but it's all i know.

by cup

coffee-80-100mg
black tea-40mg
green tea-20mg

 

[djveed]

different brews

Does anyone know the difference in caffeine content from:

1 cup drip coffee
1 cup French Press coffee (14g of grinds)
1 espresso

 

[JohnB]

Re: different brews

Does anyone know the difference in caffeine content from:

1 cup drip coffee
1 cup French Press coffee (14g of grinds)
1 espresso

Google comes up with:

6oz Drip - 90-175
Espresso - 1.5-2oz 100
Brewed?? - 80-135

 

[djveed]

So it seems that they're all pretty similar. That solves it. Thanks.

 

[JohnB]

So it seems that they're all pretty similar. That solves it. Thanks.

There is a definite variation in the amount of caffeine in each Espresso blend. Depends on the beans used I guess but some will have your eyes bugging after one & others I can drink 2-3 without getting too buzzed.

 

[coffeechem]

Its simple math:

First, caffeine content in arabica coffee hovers around 2.2% - or 2.2g per 100 grams of coffee. Since 1oz is 28.35 grams:

(2.2g caffeine/100g coffee) x (28.35g/1 oz) = 0.6237g if coffee per oz of arabica coffee.

The issue of caffeine content across both dark and light coffee really depends on how you look at the situation. Per bean, the caffeine content remains the same, but when prepared (ie brewed) it MAY be possible that darker coffee may have more caffeine, since it weighs less (more H2O loss, etc) than lighters - hence, you NEED more coffee (ie. mass) to achieve the same throw weight and thus, have more material to "extract" caffeine.

Joseph
url removed by moderator

 

[PinkRose]

Hello Everyone,

I just registered on the coffeechemistry.com website and started to explore it. There is lots of interesting stuff there (But you'll need to register if you want to see everything)

Rose

 

[CCafe]

Its simple math:

First, caffeine content in arabica coffee hovers around 2.2% - or 2.2g per 100 grams of coffee. Since 1oz is 28.35 grams:

(2.2g caffeine/100g coffee) x (28.35g/1 oz) = 0.6237g if coffee per oz of arabica coffee.

The issue of caffeine content across both dark and light coffee really depends on how you look at the situation. Per bean, the caffeine content remains the same, but when prepared (ie brewed) it MAY be possible that darker coffee may have more caffeine, since it weighs less (more H2O loss, etc) than lighters - hence, you NEED more coffee (ie. mass) to achieve the same throw weight and thus, have more material to "extract" caffeine.

Joseph
url removed by moderator

For coffee chemistry I'm a little bothered by the way you wrote this.

This is almost of myth proportions when talking about which has more caffeine light or dark roasts. To help set this post straight I'll include a quote from Roast Magazine.

Beyond selection of the green beans, the roaster is commonly thought to control one more variable in the final caffeine content of the beans: the roast level. Popular lore has always been that the darker the roast level, the lower the caffeine content. This is not really the case, as caffeine changes very little during the roasting process. Caffeine has a very stable crystalline structure with a boiling point above 600 degrees Fahrenheit, far above roasting temperatures, which rarely exceed 470 degrees Fahrenheit. This means there is very little change to the caffeine during the roasting process. The minimal amount of caffeine lost during roasting is attributable to sublimation, which is the transition of a substance directly from its solid state to its gaseous state, as commonly occurs with dry ice. Caffeine undergoes this transition at around 350 degrees Fahrenheit. Since coffee is roasted at temperatures above 350 degrees, a minimal amount of the caffeine is lost this way during the roasting process.

Although minimal caffeine is driven off or destroyed in the roasting process, the bean undergoes major changes during roasting. This can confuse the situation because the caffeine content per weight and per volume changes—not because the caffeine changes, but because the size and the weight of the bean changes. Ironically, because the bean loses weight (mostly water) during roasting, the caffeine content by weight increases, but because the bean increases in size during the roasting, the caffeine content by volume decreases.

It is fortunate that there are no requirements to label caffeine content on packages of roasted beans. So many variables contribute to the caffeine content of a single origin at a defined roast level that it is nearly impossible to predict the content without decaffeinating the bean and measuring the amount extracted. Now take differing cultivars from multiple farms and multiple countries, throw in a little robusta for an espresso blend, and you might need to put on another pot of coffee and call an organic chemist.

CAFFEINE CONTROL
Managing the Speed of the Bean
by Jim Fadden
http://www.roastmagazine.com/backissues ... ntrol.html

For the most part the differences is so small its not even worth arguing over.

 

[Ives]

I'm pretty sure this wont help, but it's all i know.

by cup

coffee-80-100mg
black tea-40mg
green tea-20mg

Thats why experts suggest green tea more than coffee or black tea because it has least number of calories in it and also helps to lose weight.

chicago boot camp

 

[CJA]

This link might help, it has a caffeine content chart...

Information about caffeine dependence