Traditionally prepared Ethiopian coffee tastes much better than the filter coffee we get in our office. Sureley, the smell of roasted coffee berries, incense and grass, the top quality of the manually-ground 100% pure Arabica coffee and the attention of the girl or woman in traditional dress make a difference. But it also involves mathematics1.
Standard office brew is prepared by pouring hot water over ground coffee (Eq. 1), a gravitational method also known as American coffee or percolation coffee2. The traditional method to prepare coffee, however, involves adding water to ground coffee and putting this over heat repeatedly (Eq. 2). The more complex method yields better results, at least for coffee.
1 Which may be considered as a sign of purity.
2 For more on coffee preparation, see Wikipedia.
Does that equation have the Ben Goldacre seal of approval?
As winter is not the prime mathematical formula season, these ones should be read as dingbats (hot water over ground coffee ;) ).
Raf – two years ago, ‘cold-brewed iced coffee’ seemed to become all the rage.. have you tried it?
hm, I wonder if this is similar what could be called “kokkaffe” (cooked coffee) in Sweden? You measure coffee and water and put it on the stove… kind of :)
btw, the second equation needs a little index of the water too, doesn’t it?! (i.e. hot or cold)
Also, in equation 1, although hot water passes over the coffee, it is axiom that cold water be put in the coffee maker, which then heats it up.
What about the Bodum? How does that figure in? Do we need some calculation of the pressure on either side of the plunger as a function of time?
*runs away from complicated integral calculus
I agree with Richard that time should likely factor into both equations, given the potential for over-extraction (for different reasons) in each method.
Since you mention the Bodum. I confess. I have exclusively prepared my Brewhome this way for 3 years and have had my Brewsomeplace other than home in this fashion when available.
Is equation 2 turkish and greek coffee too (crazy strong with grounds in the mouth + sucrose).
A lot of interesting comments here.
Mmmm. There is also, of course, the tricky question of the Vietnamese coffee I occasionally enjoy, which uses gravity filtration of hot (but probably not boiling, at least not for very long) water through dark roast grounds, onto a bed of sweetened condensed milk. The resultant two-phase mix is then stirred up and poured over ice, making a delicious drink. The physics of all this must be tremendously complex.
@Sarbjit – Turkish coffee is what I thought of for #2. The grounds between the teeth are a little irritating, yes.
What about lattes? Americanos? Cappuccinos (cappuccini?)? The potential for deriving ever-more-complicated models for these is mind-boggling.
I know really, frothy models, soy-based models! Turkish coffee’s really sugary, so it made me wonder.
I saw this paper title today and your post popped into my head Explosive Percolation in Random Networks
Which reminds me: you should invite me for coffee some time soon! ;)