Well, I know that espresso is basically a process for preparing coffee. My question is more along the lines of what the end result technically is. Is it like a concentrated coffee or something? Is Caffe Americano (watered down espresso) basically just normal drip coffee?
espresso is finely ground coffee beans brewed at a much higher pressure and temperature than coffee. The resultant product, to me, is almost but not totally completely unlike coffee. It doesn’t give me heartburn or keep me up at night.
This nice link tells us more.
http://lrs.ed.uiuc.edu/students/tchen3/espdifine.html
Right, I’ve already skimmed through that link when I searched on Google.
As I said, I know the process of espresso. And I know that the resultant product is much different than coffee. I’m trying to figure out exactly what that final product is.
Well, if you find out, let me know.
Try:
http://www.pipcom.com/~mharris/coffee.html
Near the bottom of the page, it gives a little “content” rundown. For further info, the “ways of brewing” link right at the bottom might be handy too.
-Coffeeguy
Sorry, coffeeguy, but that link didn’t help me much. I too am joining neurotik’s quest to discover how espresso is different from coffee chemically. I think the different brewing conditions must result in different chemical compounds being formed, which is why it’s so yummy and not aggravating to my stomach. Surely someone has done gas chromatography or mass spectrometry on the stuff!
Here is a list of references I found.
A good overview can be found in the June 2002 issue of Scientific American in an article titled The Complexity of Coffee.
You can find a copy in the library or purchase 30 day online access from the SCIAM archives.
It has this to say regarding the Crema:
There is also a graph which shows the optimal concentration of eleven aromatic compounds along with their associated flavors.
The article summarizes espresso thusly:
Yum!
Wait, I just need to comment on rsa’s post:
You’re saying Scientific American spells it “expresso”?!
Sheez!
Awesome, RSA! I should have guessed it was a combo of colloids and aromatic volatiles! :smack:
No, it was transcribed from a hard copy. All mistakes are mine.
Qadgop, thanks for the sarcasm.
[ul]
[li]2, 4 decadienal RANCID[/li][li]ethylgujacol SMOKE[/li][li]2-ethyl-3,5-dimethylpyrazine CHOCLOLATE[/li][li]2-ethyl-3,6-dimethylpyrazine CHOCOLATE[/li][li]2,4-nonadienal RANCID[/li][li]methylsalicilate CINNAMON[/li][li]b-damascenone TEA[/li][li]DMTS SULFUR[/li][li]isovaleraidehyde SWEET[/li][li]e-ionone FLOWERS[/li][li]linalool FLOWERS[/li][/ul]
I wasn’t raggin on ya, rsa. And I am grateful for your info.
Also - remember that the darker the roasted coffe bean is, the lower content of caffein. So the weak, brown, watery stuff you Americans persist in calling coffee is more prone to get you jittery, caggein hyped and with heart burn.
That’s the beauty of espresso - more taste, less caffein.
What is espresso? It is lifeblood. It is my breakfast, it is the coda to my lunch, the final act to my dinner, the drink of hospitality in my house, it is the alpha and the omega. I gotta go make some now.
The only time I ever tried any was at a little coffee shop at the local mall; it tasted like it was brewed rom cigarette ash. Maybe I need to look for a better place to try it.
RR
A soulmate! A soulmate! Where do you get your beans? Are the pre-roasted? Pre-ground? what type of machine do you use? I must know!!
Machine: Pump driven Delonghi, can’t read the name anymore. This is my second one. The first one died after long and faithful service. Also have two stovetop machines, a small one for two cups and a monster one for about 10.
Coffee: Pre-roasted, pre-ground. Prefer Bustelo brand, but Llave brand is very close. <<Yes I know, this is sacrilege, but I drink a LOT of espresso. I’d go broke if I drank whole-bean-gourmet coffee, I can get Bustelo or Llave for $.99 a 10 oz. package>>
Btw, do you drink your with sugar or without?
Itsa da dee;ivery serviso–you know Federolo Expresso! 
Capresso steam machine, pre-roasted espresso beans from Alterra, roasted at the store, ground each week. No sugar, no lemon peel, just espresso. I just finished a cup! Yum!
In Italian, it literally means ‘pressed out’ — steam pressure forces water vapor through the grounds and then condenses back into liquid thanks to crossing the phase boundary of that temperature-pressure curve we learned back in beginning Chem.
My question for the cognoscenti here — the espresso machine used by the baristas, where you pull the lever to force the steam? That’s kind of expensive, isn’t it? But will anything else suffice for a true espresso snob? What about the penurious lover of espresso who wants to make it at home? Would you find the results of a stovetop espresso pot acceptable? This is the Dolce Caffè pot, ingeniously designed, that boils water in the bottom half, until steam pressure forces the water vapor up through the coffee filter in the middle level, and upward through the long narrow tapering condensation funnel, until the precious liquid drops spill and sputter out a slit at the top of the funnel and collect in the top half of the pot. I love those things.