"Strong coffee doesn't equal a dark roast, merely a greater concentration of grounds to water. Also, dark roast has more caffeine by weight because it looses more water during the roasting process. However, since the beans expand it has less caffeine by volume. Since most people measure their coffee with a scoop instead of by weight lighter roasts do have more caffeine in the cup. Simple put the amount of caffeine lost in the roasting process is very minimal."  Will Rhoads

Someone said this on FB and I was just looking to evaluate and correct if needed.

Views: 78

Reply to This

Replies to This Discussion

First sentence on a technical level is true. But it depends on how your using the word. For many of our customers, dark roast is strong coffee or the alternative. That's why when they ask for a dark roast, we never really give them the answer they'd expect.
I agree with jeremiah. but dark roast will always have less caffeine (unless of course it's robusta coffee) but the longer you roast beans for the more caffeine you burn away. Compare to when making pot brownies if you let the herb sit too long and cook in the oil you burn away the thc. Same basic principle (im 99% sure about this, if I'm wrong someone please correct me)
Agreed with Will.

Forgot where I saw that discussion about caffeine lost during roast being minimal, but the source was good. Bottom line was that caffeine doesn't burn away in appreciable quantities. Will repost if I find it.

Agree also with the strong coffee not equaling dark roast and vice-versa. You can brew a weak cup of "dark roast", a strong cup of "medium roast", a bolder medium roast... But people do usually equate the two.

I actually like the "bold" descriptor better than "dark"... it cuts to what people are looking for. They don't necessarily need smoke to be there, they just don't want a cup of brown water. On the flip-side, some people that ask for "light roast" really just want something milder... which may be a darker roaster coffee. Not exactly what you get with a lightly-roasted Yirg...
I think the article you're referring to was in the May/June 2008 issue of Roast, "Under the Microscope: the Science of Coffee Roasting" by Dr. Joseph Rivera and it addressed chemical changes during the roasting process.

"Bold" kind of bums me out. I prefer "burly," since bold is best used to describe a type face or brazen behavior.

Brady said:
Agreed with Will.

Forgot where I saw that discussion about caffeine lost during roast being minimal, but the source was good. Bottom line was that caffeine doesn't burn away in appreciable quantities. Will repost if I find it.

Agree also with the strong coffee not equaling dark roast and vice-versa. You can brew a weak cup of "dark roast", a strong cup of "medium roast", a bolder medium roast... But people do usually equate the two.

I actually like the "bold" descriptor better than "dark"... it cuts to what people are looking for. They don't necessarily need smoke to be there, they just don't want a cup of brown water. On the flip-side, some people that ask for "light roast" really just want something milder... which may be a darker roaster coffee. Not exactly what you get with a lightly-roasted Yirg...
I think the guy "Will Rhoads" already did. Does anyone know who he is or if he wrote a book. Was he a friend of Illy? I'm heading out of here for the days events at the SCAA event or I would be googling now.
Joe

Joe Smith said:
I agree with jeremiah. but dark roast will always have less caffeine (unless of course it's robusta coffee) but the longer you roast beans for the more caffeine you burn away. Compare to when making pot brownies if you let the herb sit too long and cook in the oil you burn away the thc. Same basic principle (im 99% sure about this, if I'm wrong someone please correct me)
can you suggest any books on the science of coffee?

Joseph Robertson said:
I think the guy "Will Rhoads" already did. Does anyone know who he is or if he wrote a book. Was he a friend of Illy? I'm heading out of here for the days events at the SCAA event or I would be googling now.
Joe

Joe Smith said:
I agree with jeremiah. but dark roast will always have less caffeine (unless of course it's robusta coffee) but the longer you roast beans for the more caffeine you burn away. Compare to when making pot brownies if you let the herb sit too long and cook in the oil you burn away the thc. Same basic principle (im 99% sure about this, if I'm wrong someone please correct me)
There are so many I would not know where to start. I just came from the SCAA store at the SCAA convention. I wanted to buy them all but had no cash on hand.
Joe

Joe Smith said:
can you suggest any books on the science of coffee?

Joseph Robertson said:
I think the guy "Will Rhoads" already did. Does anyone know who he is or if he wrote a book. Was he a friend of Illy? I'm heading out of here for the days events at the SCAA event or I would be googling now.
Joe

Joe Smith said:
I agree with jeremiah. but dark roast will always have less caffeine (unless of course it's robusta coffee) but the longer you roast beans for the more caffeine you burn away. Compare to when making pot brownies if you let the herb sit too long and cook in the oil you burn away the thc. Same basic principle (im 99% sure about this, if I'm wrong someone please correct me)
The one coffee science book I really want to own is "Espresso coffee: The science of quality" by Rinantonio Viani (Editor), Andrea Illy (Editor). I have heard really good things about it, I just can't justify the price tag right now, since amazon has if for $88 and that seems to be the low end.

Joe Smith said:
can you suggest any books on the science of coffee?

Joseph Robertson said:
I think the guy "Will Rhoads" already did. Does anyone know who he is or if he wrote a book. Was he a friend of Illy? I'm heading out of here for the days events at the SCAA event or I would be googling now.
Joe

Joe Smith said:
I agree with jeremiah. but dark roast will always have less caffeine (unless of course it's robusta coffee) but the longer you roast beans for the more caffeine you burn away. Compare to when making pot brownies if you let the herb sit too long and cook in the oil you burn away the thc. Same basic principle (im 99% sure about this, if I'm wrong someone please correct me)
Illy's book is pretty great. I don't think I've taken much from it that has affected me in practice as a barista, but it's an interesting read if you can follow some of the chemistry. I always come away from it with some odd fact about coffee to focus on or share.
Will may have quoted it from another site.
I just found it humorous to read the facebook posting by a young man I know and then the posting of one of my employee who chimed back correcting the the mutual friend about dark coffee not always equalling strong caffeine... then this other person I do not know (Will Rhoads) posted the above which my husband found a similar article on line. My inquiry was primarily to double check the factual level of someone who was correcting my employee. After all he was quite proud to be able to enlighten his friend with the knowledge gained on the job.

Joseph Robertson said:
I think the guy "Will Rhoads" already did. Does anyone know who he is or if he wrote a book. Was he a friend of Illy? I'm heading out of here for the days events at the SCAA event or I would be googling now.
Joe

Did a quick Google search on terms "roast" and "caffeine content" and easily found that Roast article here:

CAFFEINE CONTROL
Managing the Speed of the Bean
by Jim Fadden

Here's a quick excerpt:

"...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."
Who is Jim Fadden? Google searches do not always lead to links that are credible... is this one okay? (Just trying to learn; not making comment).

That's why I am asking so I can find credible sources, so we don't learn wrong and teach our customers wrong. I thought 'the stronger the roasts the less caffeine', obviously this isn't technically true.

SO, what do you tell your customers? How do you describe your coffees to your customers?
"I want a really strong coffee, I need to wake up."
"I want a strong coffee I like a bold taste."
"I want a light coffee, I'm not really a coffee drinker."
"Do you have a coffee that's lighter in caffeine but not decaffeinated?'

Reply to Discussion

RSS

Barista Exchange Partners

Barista Exchange Friends

Keep Barista Exchange Free

Are you enjoying Barista Exchange? Is it helping you promote your business and helping you network in this great industry? Donate today to keep it free to all members. Supporters can join the "Supporters Group" with a donation. Thanks!

Clicky Web Analytics

© 2020   Created by Matt Milletto.   Powered by

Badges  |  Report an Issue  |  Terms of Service