stir a "guinness effect" espresso to avoid concentrated layer at bottom???

[fubar]

This is probably a stupid question, but please bear with me - I need a sanity check!

Short version: I dont use sugar, but am finding that if I dont stir my 60ml double shot, the last few ml. are extremely strong - as if my 60ml/30sec doppio is layered in the cup as it pours - is this my imagination - has anyone else noticed that a quick stir helps disperse that first few drops of concentrated extraction?!

Long version: Using any fresh roast/ground coffee (eg currently espresso wow from Andy - very nice!), and a reliably adjusted 30 secs/ 60ml for a double (pidd sylvia), Im getting a huge guiness effect which quickly stabilizes to a nice thick layer of persistent crema. So far, so very good. However, I kept noticing or imagining that the last sip or two were almost overpowering on the palate and thicker in mouthfeel - not unpleasant but really meaty and concentrated - so I now give it a quick stir even though its sweet enough without sugar! and the taste and mouthfeel are far more consistent through the whole drink? 

My theory FWIW: As the pour proceeds, the presence of so much froth and bubble (from C0₂ in the fresh roast I believe?) and the relatively slow pour rate means that there is relatively little or no mixing in the glass (Im using 90ml duralex) so the first extracted juice, which tends to be thick and black - the froth and bubble start about 3 seconds into the pour - stays at the bottom. Im guessing it has a higher specific gravity, so the bubbly stuff layers itself on top and a quick stir disperses it from the bottom where it lies in wait for that last (surprising!) sip...

Does this make sense to anyone? Does anyone have any references to previous reports? If not - I bags calling it the Lazarus effect and I finally have my own scientific coffee theory!

[mwatt]

Re: stir a "guinness effect" espresso to avoid concentrated layer at bottom???

Not sure about your specific gravity theory, but a shot will taste different down the demitasse. I frequently find the last sip to be the sweetest, and yes, quite punchy.

Another variable to experiment with. Pull a double, but with a demitasse under each PF spout. Drink one without a stir, drink one with a stir. See which you like best! It may change depending on whats in the grinder

Had an amazing Limu a few weeks ago that was awesome with a quick stir.

[fubar]

Re: stir a "guinness effect" espresso to avoid concentrated layer at bottom???

Ive added a poll to this topic - Im curious how many people (like Michelle) have noticed the last few sips of an unstirred espresso tend to be more concentrated - the first few mL extract is probably thicker and more dense, so stirring makes the drink more uniform (and for some, that means more delicious!)?

[scoota_gal]

Re: stir a "guinness effect" espresso to avoid concentrated layer at bottom???

Fubar...here is what I have noticed...(and no reaction from the back stalls about this one thanks! )

When I run a few shots through the machine for our iced coffees, I put them into a container which goes into the fridge to chill. By the time I get to the last few shots in the container, I have seen a very heavy and thick liquid on the bottom. Usually, I just pour the thinner liquid on the top into my iced drinks and the thick stuff goes down the sink.

Ive always wondered why there is such thick treacle like substance at the bottom of this container...though I do wonder if its not just the coffee oils that have gone solid in the cool fridge?

Im keen to hear what others say as well...

[Dimal]

Re: stir a "guinness effect" espresso to avoid concentrated layer at bottom???

Ive always wondered why there is such thick treacle like substance at the bottom of this container...though I do wonder if its not just the coffee oils that have gone solid in the cool fridge?

Hmmm,

Thats interesting Scoots... Will try something similar and check out the "treacle". Maybe youve inadvertently discovered something quite unique 8-)

Mal.

[fubar]

Re: stir a "guinness effect" espresso to avoid concentrated layer at bottom???

Interesting - thanks everyone.  Maybe this is a useful observation, although from the poll, it seems that most repondents actually like the last few drops being concentrated! I must say, I actually prefer the more uniform stirred beverage, but de gustibus non disputandem est.

For the record, this really only seems to happen when the coffee gods are smiling, the 3 Italian Ms are in harmony, and the pour is blessed with a substantial guinness effect - I had some supermarket beans in an emergency situation (!) the other week - no guinness effect, no layering, and not much good either.

My guess is going to be that if you stir that container thoroughly before refrigerating it, the thicker goopy first extract stuff will be dispersed, and maybe the iced coffees will be more uniform. Not sure about the oil separating out theory - wouldnt that be less dense and float to the top? At least thats what happens to the fat in my refrigerated chicken stock

[Thundergod]

Re: stir a "guinness effect" espresso to avoid concentrated layer at bottom???

the 3 Italian Ms are in harmony

I thought there were 4. :-?

[flynnaus]

Re: stir a "guinness effect" espresso to avoid concentrated layer at bottom???

the 3 Italian Ms are in harmony

I thought there were 4.  :-?

Yes but there is a world-wide recession so they had to cut back

[fubar]

Sugarless espresso stirrers of the world, unite! Down with the superfluous Ms!

I thought there were 4 

Might have to start another thread, but as OP, I think I can claim the right of reply without risk of thread hijacking

Fair enough - however, perhaps the recession is already over - it seems the Ms are multiplying like rabbits - this from a nameless manufacturer:

Traditionally in Italy people have always spoken of the 3 Ms: "Macchina" (the machine), "Miscela" (the blend), "Mano" (the hand and expertise of the barista). A fourth M was added on subsequently: the coffee grinder ("Macinadosatore"). And we have in recent years added on the fifth mandatory M: "Manutenzione" (service and maintenance).So we can safely say that if all these factors fall into place properly, your customers can be served a perfect espresso, cappuccino or latte.

AFAIK, I first heard of 3 but the grinder manufacturers got their collective noses out of joint and promulgated 4 Ms - Im old fashioned and I think macchina includes all the electro-mechanical apparatus - both the grinder and the espresso machine - the definition in a handy on line Italian dictionary suggests that any apparatus (apparechio) that transforms energy to do useful work is una macchina:

macchina
noun feminine macchina
1  apparecchio dispositivo congegno che trasforma energia e/o compie un lavoro
macchina fotografica
macchina del caffè
macchina per / da cucire
macchina per / da scrivere
2  vettura auto lautomobile
andare in macchina
comprare una macchina nuova
3  apparato organusmo complesso di organi o poteri coordinati
la macchina dello Stato
la macchina di un partito politico
4  automa persona che agisce meccanicamente
Quando lavora è una macchina.
macchina elettrica
che trasforma energia meccanica in energia elettrica e viceversa
macchina da presa
apparecchio per la ripres adi immagini cinematografiche
macchina della verità
apparecchio con cui si registrano le reazioni dellinterrogato per valutarne la sincerità
a macchina
non artigianalmente

Kernerman Italian Learners Dictionary © 2008 K Dictionaries Ltd All rights reserved.

[Thundergod]

Re: stir a "guinness effect" espresso to avoid concentrated layer at bottom???

"Manutenzione" (service and maintenance)

Sorry; I wont accept this one at all.
It would fall under the first "M".

Im quite happy to accept your first 3 if you want to ignore the 4th one.