4 ms·

Direct electrochemical black coffee quality appraisal using cyclic voltammetry

62 points by bookofjoe 6mo ago

zeristor 6mo ago
How long before James Hoffman finds out about this. Waiting for him to appear in the YouTube shorts Brooklyn Coffee shop now I think about it.
- SkiFreeWin3 6mo ago
  It took me a few vids to warm up to his presentation style and the production style, but now anyone else doing coffee vids seems like a total amateur/influencer/YT rusher. Early Hoffman coffee competitions were the proof point for me that he’s not simply an influencer entrant. His presentation still is still a bit forced and orchestrated to me, but at least I believe he’s smart and has interest in the craft.
  - jitl 6mo ago
    he’s adorable what’s not to love??
    - zeristor 6mo ago
      Is his quiff a side effect of his prodigious coffee intake? I’m waiting for his eyes to glow blue, and he perfects the ability to fold space and time.
  - zimpenfish 6mo ago
    > Early Hoffman coffee competitions were the proof point for me that he’s not simply an influencer entrant. That and owning a coffee roasting company?
- andreareina 6mo ago
  What does this offer over the refractometer he already has?
  - chronogram 6mo ago
    It says that refraction does not cover everything. > By sampling features in the electrochemical response that are affected by the ensemble chemical composition of the coffee rather than measuring the concentrations of individual molecules, this approach captures quantitative information about both roast color and beverage strength. These two properties drive the sensory profile of the beverage, thereby allowing this analytical technique to exceed the insights provided by refractive index measurements and provide additional quality information that correlate with flavor.
  - Aaargh20318 6mo ago
    > we show that cyclic voltammetry can be used without any additional sample preparation Even if it offered no additional data over a refractometer just the fact can be used directly without any sample preparation would be a huge win. Refractometers are a PITA to use.
s0rce 6mo ago
I sent this to our electrochemist at work, maybe if we have some time we can test the coffee in the breakroom.
- xingped 6mo ago
  The title says "quality" but the summary seems to say it only measures the "strength" oand "darkness of roast". Certainly won't measure how good it tastes. Given these are the two properties purportedly measured, I imagine you'd get the same results regardless of tastiness and age of the coffee or beans.
  - TeMPOraL 6mo ago
    > Given these are the two properties purportedly measured, I imagine you'd get the same results regardless of tastiness and age of the coffee or beans. Right, but another way of putting it, it might provide useful signal if you hold "age of the coffee or beans" and other such factors constant :).
- anon84873628 6mo ago
  Their lab has been playing with this for a while: https://sca.coffee/sca-news/25/issue-18/amped-up-using-electricity-to-detect-and-quantify-molecules-in-brewed-coffee https://sca.coffee/sca-news/25/issue-18/amped-up-using-elect...
userbinator 6mo ago
I suggest "black coffee electrochemical quality appraisal"; as-is, it made me wonder what "electrochemical black coffee" is.
- euroderf 6mo ago
  It has electrolytes!
- TeMPOraL 6mo ago
  Technically, everything is electrochemical.
advisedwang 6mo ago
I suppose this might be useful for making full-auto coffee machines that can self-adjust parameters like grind size, water:coffee ratio, tamping strength (for espresso style machines) etc. Although there's plenty of things to measure already, they don't really directly check correct brewing. This could help improve a lot.
fsckboy 6mo ago
>Here we show that cyclic voltammetry can be used without any additional sample preparation to directly measure the strength of a coffee beverage and, separately, how dark the coffee has been roasted; these two properties are implicated in the sensory profile of the beverage. those two properties do not even touch on the quality of the beans, nor how those flavors are developed and maintained through roasting. measuring the darkness of roast does not tell you how dark the coffee should have been roasted for optimum flavor profile. I'm not aware that it can be done analytically, it requires trained tastebuds, and in my experience, tastebuds trained on many coffees over time (a sort of 10,000 hours type idea, probably needs neuroplasticity); most roasters have a sort of narrow "tunnel vision" based around their own coffees which they taste relentlessly. to actually taste delicious coffee it needs to cool down quite a bit, below 130F 55C which is not very hot. I understand the pleasure of a hot cup of coffee, but that pleasure is not flavor pleasure.
- anon84873628 6mo ago
  Yes, but once your target roast and strength is dialed in, this can easily be used for quality control. Keep in mind that the coffee industry is very different than home specialty brews.
- Xmd5a 6mo ago
  Isn't this whole approach to coffee similar to audiophily? I'm asking this as an avid coffee drinker (fancy grains, with a fancy machine) and an appreciator of headphones as well : when should one stop the quest for perfection? For headphones, anything beyond 400-500$ is not reasonable, since past this limit you start chasing gains that are barely perceptible or are a question of taste and you'll be able to find equivalent headphones that cost less. Where do you draw the limit personally ?
  - ricardobayes 6mo ago
    I think it's very comparable: the current dialogue in "coffee" circles revolve around the usage of "steamed water" that supposedly improves the taste. I remember similar discussions around cables in audio circles.
anon84873628 6mo ago
From the lab of Christopher Henson at University of Oregon. They've done lots of work on coffee. Doran and Chris also host a podcast called Coffee Literature Review, where they invite a guest from the coffee industry and discuss a scientific paper connected to coffee somehow: https://podcasts.apple.com/us/podcast/coffee-literature-review/id1737907375 https://podcasts.apple.com/us/podcast/coffee-literature-revi... At the SCA Expo a few years ago, they were doing electrochemistry on brewed coffee to measure caffeine content, and also change the flavor in weird ways. This latest paper seems to build on previous experiments in a similar vein: https://sca.coffee/sca-news/25/issue-18/amped-up-using-electricity-to-detect-and-quantify-molecules-in-brewed-coffee https://sca.coffee/sca-news/25/issue-18/amped-up-using-elect...
RobotToaster 6mo ago
Amazing that the article describes what coffee is in detail, but never describes what "cyclic voltammetry" is. For those who are as ignorant as I https://en.wikipedia.org/wiki/Cyclic_voltammetry https://en.wikipedia.org/wiki/Cyclic_voltammetry
- fuzzfactor 6mo ago
  From Wikipedia: >The electrodes are immobile Not always as immobile as they could be. >Common materials for the working electrode include glassy carbon, platinum, and gold. Using mercury instead has characteristics not exactly like the others: https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/25%3A_Voltammetry/25.02%3A_Voltammetric_Instrumentation https://chem.libretexts.org/Bookshelves/Analytical_Chemistry... I would want to repeat the experiments using a dropping mercury electrode and see how that acts.
picsao 6mo ago
[dead]
camillomiller 6mo ago
* laughs in barely cleaned Italian moka *
unit149 6mo ago
[dead]

62 points by bookofjoe 6mo ago

How long before James Hoffman finds out about this. Waiting for him to appear in the YouTube shorts Brooklyn Coffee shop now I think about it.

SkiFreeWin3 6mo ago
It took me a few vids to warm up to his presentation style and the production style, but now anyone else doing coffee vids seems like a total amateur/influencer/YT rusher. Early Hoffman coffee competitions were the proof point for me that he’s not simply an influencer entrant. His presentation still is still a bit forced and orchestrated to me, but at least I believe he’s smart and has interest in the craft.
- jitl 6mo ago
  he’s adorable what’s not to love??
  - zeristor 6mo ago
    Is his quiff a side effect of his prodigious coffee intake? I’m waiting for his eyes to glow blue, and he perfects the ability to fold space and time.
- zimpenfish 6mo ago
  > Early Hoffman coffee competitions were the proof point for me that he’s not simply an influencer entrant. That and owning a coffee roasting company?
andreareina 6mo ago
What does this offer over the refractometer he already has?
- chronogram 6mo ago
  It says that refraction does not cover everything. > By sampling features in the electrochemical response that are affected by the ensemble chemical composition of the coffee rather than measuring the concentrations of individual molecules, this approach captures quantitative information about both roast color and beverage strength. These two properties drive the sensory profile of the beverage, thereby allowing this analytical technique to exceed the insights provided by refractive index measurements and provide additional quality information that correlate with flavor.
- Aaargh20318 6mo ago
  > we show that cyclic voltammetry can be used without any additional sample preparation Even if it offered no additional data over a refractometer just the fact can be used directly without any sample preparation would be a huge win. Refractometers are a PITA to use.

s0rce 6mo ago

I sent this to our electrochemist at work, maybe if we have some time we can test the coffee in the breakroom.

xingped 6mo ago
The title says "quality" but the summary seems to say it only measures the "strength" oand "darkness of roast". Certainly won't measure how good it tastes. Given these are the two properties purportedly measured, I imagine you'd get the same results regardless of tastiness and age of the coffee or beans.
- TeMPOraL 6mo ago
  > Given these are the two properties purportedly measured, I imagine you'd get the same results regardless of tastiness and age of the coffee or beans. Right, but another way of putting it, it might provide useful signal if you hold "age of the coffee or beans" and other such factors constant :).
anon84873628 6mo ago
Their lab has been playing with this for a while: https://sca.coffee/sca-news/25/issue-18/amped-up-using-electricity-to-detect-and-quantify-molecules-in-brewed-coffee https://sca.coffee/sca-news/25/issue-18/amped-up-using-elect...

userbinator 6mo ago

I suggest "black coffee electrochemical quality appraisal"; as-is, it made me wonder what "electrochemical black coffee" is.

euroderf 6mo ago
It has electrolytes!
TeMPOraL 6mo ago
Technically, everything is electrochemical.

advisedwang 6mo ago

I suppose this might be useful for making full-auto coffee machines that can self-adjust parameters like grind size, water:coffee ratio, tamping strength (for espresso style machines) etc. Although there's plenty of things to measure already, they don't really directly check correct brewing. This could help improve a lot.

fsckboy 6mo ago

>Here we show that cyclic voltammetry can be used without any additional sample preparation to directly measure the strength of a coffee beverage and, separately, how dark the coffee has been roasted; these two properties are implicated in the sensory profile of the beverage. those two properties do not even touch on the quality of the beans, nor how those flavors are developed and maintained through roasting. measuring the darkness of roast does not tell you how dark the coffee should have been roasted for optimum flavor profile. I'm not aware that it can be done analytically, it requires trained tastebuds, and in my experience, tastebuds trained on many coffees over time (a sort of 10,000 hours type idea, probably needs neuroplasticity); most roasters have a sort of narrow "tunnel vision" based around their own coffees which they taste relentlessly. to actually taste delicious coffee it needs to cool down quite a bit, below 130F 55C which is not very hot. I understand the pleasure of a hot cup of coffee, but that pleasure is not flavor pleasure.

anon84873628 6mo ago
Yes, but once your target roast and strength is dialed in, this can easily be used for quality control. Keep in mind that the coffee industry is very different than home specialty brews.
Xmd5a 6mo ago
Isn't this whole approach to coffee similar to audiophily? I'm asking this as an avid coffee drinker (fancy grains, with a fancy machine) and an appreciator of headphones as well : when should one stop the quest for perfection? For headphones, anything beyond 400-500$ is not reasonable, since past this limit you start chasing gains that are barely perceptible or are a question of taste and you'll be able to find equivalent headphones that cost less. Where do you draw the limit personally ?
- ricardobayes 6mo ago
  I think it's very comparable: the current dialogue in "coffee" circles revolve around the usage of "steamed water" that supposedly improves the taste. I remember similar discussions around cables in audio circles.

anon84873628 6mo ago

From the lab of Christopher Henson at University of Oregon. They've done lots of work on coffee. Doran and Chris also host a podcast called Coffee Literature Review, where they invite a guest from the coffee industry and discuss a scientific paper connected to coffee somehow: https://podcasts.apple.com/us/podcast/coffee-literature-review/id1737907375 https://podcasts.apple.com/us/podcast/coffee-literature-revi... At the SCA Expo a few years ago, they were doing electrochemistry on brewed coffee to measure caffeine content, and also change the flavor in weird ways. This latest paper seems to build on previous experiments in a similar vein: https://sca.coffee/sca-news/25/issue-18/amped-up-using-electricity-to-detect-and-quantify-molecules-in-brewed-coffee https://sca.coffee/sca-news/25/issue-18/amped-up-using-elect...

RobotToaster 6mo ago

Amazing that the article describes what coffee is in detail, but never describes what "cyclic voltammetry" is. For those who are as ignorant as I https://en.wikipedia.org/wiki/Cyclic_voltammetry https://en.wikipedia.org/wiki/Cyclic_voltammetry

fuzzfactor 6mo ago
From Wikipedia: >The electrodes are immobile Not always as immobile as they could be. >Common materials for the working electrode include glassy carbon, platinum, and gold. Using mercury instead has characteristics not exactly like the others: https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/25%3A_Voltammetry/25.02%3A_Voltammetric_Instrumentation https://chem.libretexts.org/Bookshelves/Analytical_Chemistry... I would want to repeat the experiments using a dropping mercury electrode and see how that acts.

picsao 6mo ago

[dead]

camillomiller 6mo ago

* laughs in barely cleaned Italian moka *

unit149 6mo ago

[dead]