trickydicky wrote:Without wishing to spark an anthropomorphic debate about life, the universe and everything, it seems unlikely we have stumbled on the optimum espresso so early in history. There may be extraction conditions that could give an even better espresso.

An even better coffee I can (at a stretch) conceive of, but isn't "espresso" defined as such by an agreed range of extraction conditions with relatively clear limits?

Sorry, I'm not up to speed yet on strict definition of espresso. But I will look it up. Learning is good

I was meaning espresso in the general sense of a short black coffee with a crema made by squeezing hot water through coffee grounds under high pressure

A couple months ago I was doing a bit of research on coffee through various databases available through my university. I turned up a lot of references to this organization:

http://www.asic-cafe.org/

Keep in mind these articles are quite technical and there is a membership fee of 200 euro/year to access them.

Did you see this recent HB thread -- interesting article including info on Maillard reactions etc? -- Molecular Gastronomy: A New Emerging Scientific Discipline

and on the science of developing coffee aroma compounds during roasting, there is a thesis available online: http://e-collection.library.ethz.ch/ese ... 731-02.pdf

and maybe of more general interest: http://espressoitaliano.org/doc/EIC%20- ... -%20LQ.pdf re specs for the Istituto Nazionale Espresso's idea of Italian espresso

and searching http://pubs.acs.org/ always turns up dozens of fascinating-looking dense articles

KScarfeBeckett wrote:An even better coffee I can (at a stretch) conceive of, but isn't "espresso" defined as such by an agreed range of extraction conditions with relatively clear limits?

I'm surprised how narrow the definition is according to Istituto Nazionale Espresso Italiano:

The following are some important
conditions to obtain Espresso Italiano - though these
alone would not be adequate to fulfil the quality
requirements:
• Necessary portion of ground coffee 7 g ± 0,5
• Exit temperature of water from the unit 88°C ± 2°C
• Temperature of the drink in the cup 67°C ± 3°C
• Entry water pressure 9 bar ± 1
• Percolation time 25 seconds ± 2,5 seconds
• Viscosity at 45°C > 1,5 mPa s
• Total fat > 2 mg/ml
• Caffeine < 100 mg/cup
• Millilitres in the cup (including foam) 25 ml ± 2,5

I'm not confident I've made very many officially compliant espressi

Thanks to those who have posted references, including the great molecular gastronomy paper

As a highly digestible and usable molecular gastronomy read, I can wholeheartedly recommend the following title by Harold McGee - On Food And Cooking

It profoundly changed the way I understand, cook and appreciate food

The Istituto describes standards for "Italian espresso", not "espresso", presumably towards preserving it as part of (traditional, commercial, national-pride, touristic?) Italian food culture, perhaps in response to "espresso" being ever stretched elsewhere, by Starbucks et al., by Third Wave or Pacific Northwest trends ... So their definition might be more useful viewed as a point of old-school orientation rather than a set of constraints.

I agree, that McGee book is great fun