Does dark roast coffee have less caffeine than light roast?

It really depends on how you measure the caffeine. When coffee is roasted the beans lose some water content (somewhere in the 20% range give or take a few percent). At the same time it is losing weight it is gaining size. This leads to a situation that makes answering this question a little interesting.

Assuming all other variables are the same, if you measure by weight you actually have more caffeine in dark roast because the water loss is faster than the minimal caffeine loss during roasting. If you measure by volume you have less caffeine because the beans expand as they roast. This seems to confuse some people so let me restate the above. If you measure your coffee using a scoop you will have less caffeine per cup using dark roast coffee. If you measure your coffee by weight you will have more caffeine per cup using a dark roast. The difference one way or the other is small. If you are buying a cup of coffee and the coffee is measured by weight (common with pre-packed coffee used in many offices and some restaurants) then dark roast will have slightly more caffeine. If you buy a cup and the restaurant measures by volume (common when coffee is fresh ground and measured on the fly) then light roast will be slightly higher in caffeine simply because you will have more coffee grounds. This is really only an issue if you are talking about two identical coffees and even then the differences are small. It is conceivable if you are comparing two available brewed coffees that a difference in varietals between them could make the have as much effect as the roast and the preparation method will almost certainly had a larger effect than the roast level or varietal. If there is a Robusta in one of the coffees it is almost guaranteed to have more caffeine. This is mostly an academic discussion because the differences in caffeine content are relatively small.



Are you so idiotic that you

Are you so idiotic that you can't figure out what he was trying to say? 


Cool, you found a typo......I'm surprised you don't loose your mind being so anal.

LMAO! That is all.

LMAO! That is all.



Really.........who goes by

Really.........who goes by the weight?  As far as I know, and have been in coffee for six years now, the darker and longer the roast there is more caffeine roasted out but a stronger and more robust flavor, and the lighter and shorter the roast, the more caffeine you retain, but of course lighter and brighter notes.  Darker roasts will never have more caffeine than lighter roasts.  Now if you want to get into espresso, that is a whole different ballgame.

I actually do my coffee by

I actually do my coffee by "feel" (so I guess weight). I pour it in the basket until it looks/feels right. I'm too lazy to have a separate scooper or use a spoon b/c then I'd have to wash it. Just wanted to point out that "weight" doesn't always means that it was measured on a scale. An open mind makes that coffee moment more enjoyable in the morning

If you go by looks of how

If you go by looks of how much coffee, then thats probably volume and not weight. I do my coffee by weight. Many people have a magic ratio of water, beans etc. 

really...six years?

really...six years?

I looked all over google for

I looked all over google for it!! Thanks for the info..pfff! :)

I think the most relevant

I think the most relevant comparison between dark and light roasts of the same bean would be the mg of caffeine per cup of brewed coffee of the same subjective strength. I roast my own. Lightly roasted coffee is more acidic and bright tasting but also thinner in body, so I tend to have to use a bit more. Darker-roasted has more of that familiar smoky and bitter taste. You can use a bit less in the filter. So, the darker roast feels fuller, but the lighter roast has comparatively more kick in the cup. Anecdotal evidence only.

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