13
votes
Accepted
Theobromine in coffee
According to the Dr. Duke's Phytochemical and Ethnobotanical Databases, Coffee Arabica has one of the largest amount of theobromine in its seed (20 ppm). However, this amount is just a bit more than 1/...
- 7,678
9
votes
Is it good to have the "floating oil" on the surface of some coffee drinks?
The amount of oil in your coffee correlates to what is called the "body"? This is the "fullness" that you feel of the coffee in your mouth. Like the difference between a light cake and fudgey brownie. ...
8
votes
Accepted
Is it good to have the "floating oil" on the surface of some coffee drinks?
Nice question. A similar myth has been arisen for Turkish coffee pot; such as it should be cleaned only with water to keep the greasy surface made with coffee oil.
Partly correct, partly not. ...
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7
votes
Warm Brew Coffee?
Well I'm a chemist, but I can't say I'm an expert at scientific coffee extraction; take what I've got to say with a grain of salt.
Whenever you are extracting something into water, the temperature ...
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7
votes
Why do some grounds float and others sink when brewing by pour over
Bean density varies dramatically with roast level. The more roasted a bean is, the less dense it becomes. My guess would be that less dense beans would have more of a tendency to float and more ...
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7
votes
Is black coffee a solution, a colloid or a suspension?
That depends how the coffee is prepared.
Coffee prepared via the drip method is typically a solution. You can dilute it as much as you like and will never find suspended solids. Coffee prepared in ...
- 1,567
5
votes
Theobromine in coffee
I suspect the reason is that theobromine is much less soluble in water than caffeine. A forum post is here.
Caffeine – 21600mg/L water
Theobromine – 330mg/L water
So potentially the grounds have ...
- 246
5
votes
Accepted
Does coffee really stunt your growth?
No. That coffee (or caffeine or anything else in coffee) would stunt growth is a debunked myth.
Here's an article from the New York Times that cites a small university study that showed no relation ...
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4
votes
Warm Brew Coffee?
There are a few principles involved here (a chemical engineer's perspective on leaching - essentially coffee brewing is just that).
As Eli mentioned, solubility in water for most materials increases ...
- 41
4
votes
Accepted
How much "coffee" is there in my cup?
This is discussed in many different contexts many times, I assume. So, I can say not a very strange question in essence.
I advise you to check a previous answer first. It includes a very nice chart ...
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4
votes
Quantifying flavor differences between varieties?
Sort of...
These links, including the redesigned coffee lexicon might help answer your question
http://worldcoffeeresearch.org/images/pdfs/WCR_Sensory_Lexicon_Edition_1_2016.pdf
https://en.wikipedia....
- 400
3
votes
Can I reduce harmful terpenes?
Terpenes are the lipids (oils) that give the main flavor to your cup. Therefore, you don't want to reduce them normally. However, if you really want to reduce them, best choice is, as stated thick ...
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3
votes
Why do some grounds float and others sink when brewing by pour over
One thing to keep in mind is that coffee beans contain CO2. This causes grounds to float and foam. If the beans don't have any CO2 they won't float. This is also a sign that they have gone stale.
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2
votes
Is stale coffee less healthy for you than fresh coffee?
Disclaimer: Lately, I was checking some unanswered questions. This one stands for a while. So, I decided to use the advantages of sitting in an academic office and sought the academic databases I can ...
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2
votes
Why do aeropress columns get abrasions, or scars, near the top?
A couple years ago I emailed AeroPress because I had gone through two presses with a similar problem. In my case, the cylinder had developed heavy abrasions that affected the plunger seal. Here's my ...
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2
votes
Why do aeropress columns get abrasions, or scars, near the top?
However I cannot understood the scars definitely, I would like to offer a solution to the scars I thought:
There is a possibility that coffee grounds may stick to the rubber ring and scratch the ...
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2
votes
Could light transmittance be used to timely determine extraction?
Refractometers are widely used to measure the opaqueness of the coffee during brewing to timely determine the extraction time.
Spectrophotometers are used to measure color instead of opaqueness. They ...
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2
votes
Accepted
Using Arabica coffee beans for making instant coffee
The process should be quite the same. At least, according to this wholeseller's website.
As far as I understand this company sells 100% Arabica or Robusta OEM instant coffee.
For example, the well-...
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2
votes
What acids are there in coffee?
Funny I should come across this topic tonight, as I'm reading a book right now about the science behind making coffee as a commodity, a beverage and an art form.
One particular sentence from the book ...
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2
votes
What acids are there in coffee?
Note: I leave out a lot of the details of espresso shot extraction and just mention the major points of troubleshooting so don't flame me =p
Acidity is always tricky when you talk coffee because ...
- 1,364
2
votes
Accepted
What type of coffee maker creates the most coffee scent?
If you want a lot of scent, you will want to make sure that nothing stops evaporation - so no lid and a large surface area are paramount.
The classic method would be hand-filtered pour-over, which ...
- 4,053
2
votes
does adding powdered creamer or milk to coffee make the coffee more potent?
No. Powdered milk is just pasteurized milk that has been dehydrated. There are various processes used to dehydrate milk, and higher heat methods tend to change the molecular structure of the milk more ...
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1
vote
What type of coffee maker creates the most coffee scent?
I believe coffee lovers consume coffee to be able to drink that smell. I just want to add to Stephie's answer where that smell comes from.
While roasting, during Maillard reaction, the little pores ...
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1
vote
Effects of coffee consumption on testosterone production
In short, caffeine may increase "Sex Hormone Binding Globulin" which results decreased levels of testosterone in both men and women.
However, I don't know how effective it is. Or if this decrease is ...
- 7,678
1
vote
What acids are there in coffee?
I'm not sure if I have understood the question clearly. I will give it a try.
For espresso making, the temperature is not directly controlled by the barista, but by the espresso machine. So, you ...
- 7,678
1
vote
Could light transmittance be used to timely determine extraction?
I know it's down a different line (I like the idea of using light though) but the most common way to test proper extraction is to perform a TDS (Total Dissolved Solids) test. This is the industry ...
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1
vote
Warm Brew Coffee?
I think what your idea would lead to a more bitter taste. Simply because it would be very easy to overdo the time needed. If the beans over extracted you would have lukewarm bitter coffee. You would ...
- 11
1
vote
Warm Brew Coffee?
Your hypothesis sounds interesting. Try it.
Traditionally speaking though, these factors are what affect the characteristics that you are concerned about:
Bitterness - affected by degree of roast. ...
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1
vote
Warm Brew Coffee?
How to Brew Cold Brew Coffee in Only Two Hours
and other similar recipes all recommend using the sous vide method at 65°C (150°F) for 2 hours (in a jar or zip-lock bag), then pouring the result ...
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1
vote
Warm Brew Coffee?
I have been doing this for a long time, it definitely varies with the roasting level and the bean Varity.
I Warm brew my coffee for about 30 mins in 120 degree water. I use a light roast of ...
- 11
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