erics wrote:You keep giving people ideas, Andy.

No doubt.

He needs to collect residuals.

erics wrote:http://www.asic-cafe.org/htm/CSA/alert_item.php?ItemID=255

Lots of interesting papers on that site. But I guess it cost 200 Euros to get access to them.

narc wrote:Considering different ramp up profiles, pressure profiles during extraction, pressure range during extraction, ideal preinfusion time and total extraction time needs to be tweaked to the machine.

I agree 100%!

Andy S: Despite my earlier post (http://www.home-barista.com/tips/brewing-ratios-for-espresso-beverages-t2402-80.html#73563), I agree 100% re. keeping things simple. Your proposal for using normalized brew ratios, though it looks at only one aspect of what defines an espresso shot, is nevertheless a great contribution to the vocabulary, and its very simplicity is indeed its main conceptual strength. To add other parameters such as brew times or temps can never really, as you so correctly say, completely define the shot.

The act of pulling an espresso can either be made into an act so complicated, with it's various brew temps, boiler pressures, tamping pressures, degree of grind, degree of roast, distribution techniques, etc. to attend to, that taking a completely "left brain" approach is bound to convince one that pulling a good shot is simply not possible. (Much like trying to teach someone how to tie a necktie over the phone...) On the other hand to take a completely "right brain" approach, that is to be guided by one's sensory experience from the cup alone, is not likely to lead one in the correct direction either.

Rather by looking at pulling an espresso as an act of craft, neither 100% art, nor 100% science, seems to me to strike an appropriate balance. And in this regard your brew ratio concept can help us "declutter" ever so slightly the various parameters that we may otherwise attend to, by reducing the combination of the dose, and the volume of extraction, into a single normalized parameter.

Firstly:
I am drawn to the 'baristas percentage' idea, but only theoretically. In bread, the various ingredients might (I don't know, I'm not a baker) actually sum, such that a baker's percentage (total) means something irrespective of the ingredient list. With espresso, I don't think that is the case. The BR is a good way of pidgeonholing drinks with quite distinct flavour profiles. If you generalise it to all ingredients it loses that meaning.

Example 1: A (short) long black with 15g water + 15g espresso made from 15g coffee is not equivalent to a (50%) normale, though they both have the same BR. (Though a cafe crema for instance might well taste quite similar to a lungo + water.)

Example 2: 15g milk + 15g espresso from 15g coffee bears very little resemblance to a normale in any measure except size.


Generally:
I really like the BR, and I love the idea that one day I might be able to go to any cafe and be able to decide whether I want a normale or a ristretto (the better cafes in Australia seem to be moving towards standard shots so dense and flavoursome that asking for a ristretto only really means getting a smaller, colder shot of the same).
I agree with the sentiment, however, that there seems to be an axis missing. I'm not convinced yet that time is it.

AndyS wrote:Lots of interesting papers on that site. But I guess it cost 200 Euros to get access to them.

http://www.ingentaconnect.com/content/j ... 4/art00006

More like 32 USD without tax.

True, but we've become virtually spoiled -- if it isn't on-line, it doesn't exist.

erics wrote:Most, if not all, papers from the Journal of the Science of Food & Agriculture are available from the appropriate library of your local engineering school.

Not everybody is from US

ozzyymclaren wrote:Turkish people unfortunately dont have lots of knowledge about [Turkish coffee]

The ones I met, Istanbul academic education elite - not necessarily rich, knew everything about it. Very critical to quality of anything food and drink. Comparable to Italian food/drink and French food/wine tradition.

ozzyymclaren wrote:and when its come to brewing turkish coffee [Turkish people] use pre grounded coffee.

I once received a pack that was brought to me in the Netherlands from Istanbul, "from the best roaster in Istanbul", and had been traveling a few days in a special brown paper bag. We got apologies as to lack of freshness when it was presented. I was surprised actually how fresh the grind still was and hypothesized the fineness of the grind would block evaporation of aroma from the coffee and oxygen coming in.

Regards
Peter