how to get/test the right pressure for espresso

#1: Post by **jovial** » November 6th, 2006, 6:17 am

Hi Guys,

I've only just got a espresso machine at home (it's a Morphy Richards model 47570), but i'm not having great success at making the perfect espresso.

My main trouble is that coffee is extracted very quickly... coffee is therefore somewhat watery, and lacks crema

The manufacturer's spec says the machine is capable of producing 15bar.... i have no idea if that's the case in practice or not.

so far my findings have been as follows:

1. usually coffee is displaced after i remove the filter holder from the espresso machine....
some of the coffee even sticks to the bottom of the espresso machine, which later gradually falls off on the tray.
but the coffee ground does turn black in the filter.
coffee starts to appear 4 seconds after i press the "espresso" button and fills the two ounce cups in 5 to 6 seconds (too fast i recon)

2. i thought i wasn't packing the coffee enough and maybe that was the reason for quick channeling and coffee displacement in the filter...
so i put more coffee and packed it harder.... this time the coffee hadn't displaced but it was noticeable that the steam/water hadn't gone through the entire coffee (some middle parts were still brown)... coffee did channel through quickly again.

it's worth mentioning that after i switch off the "espresso" button and try to release the filter holder from underneath the machine it often releases some pressure or air, is this normal?

I'm not a professional, so please feel free to ask me questions if i've left out anything important.

i hope someone can guide me here to make a better use of my machine.... and if these are just the signs of a bad machine, please let me know to return it back asap.

many thanks for your time,
Shane

#2: Post by **cannonfodder** » November 6th, 2006, 6:47 am

What type of coffee and grinder are you using. It sounds like your grind is way off.

November 6th, 2006, 9:10 am

i'm using a pack of "Lavazza Qualita Rossa Ground Coffee", bought from a local store.

i was wondering... how high should i fill the filter with coffee?
i've used one full dessert spoon for single filter cup, and it doesn't fill it to the top.
i think i can squeeze 1.5 dessert spoons of coffee into a single cup.... not sure if it's the right thing to do though.

basically, should the tapped coffee (in the filter) be also a barrier to the twisting and tightening of the filter holder underneath the machine...
or should it be just the filter holder than restricts this twist?

#4: Post by HB » November 6th, 2006, 10:02 am

jovial wrote:I've only just got a espresso machine at home (it's a Morphy Richards model 47570), but i'm not having great success at making the perfect espresso.

Searching on the web, that looks like a rebadged Krups entry-level espresso machine, more than likely using a pressurized portafilter.

jovial wrote:i'm using a pack of "Lavazza Qualita Rossa Ground Coffee", bought from a local store.

As is frequently pointed out in threads like Use preground coffee while saving for an espresso grinder?, the grinder is more important than the espresso machine; the freshness of the coffee is even more important.

i was wondering... how high should i fill the filter with coffee? ... basically, should the tapped coffee (in the filter) be also a barrier to the twisting and tightening of the filter holder underneath the machine... or should it be just the filter holder than restricts this twist?

Some espresso machines respond well to "updosing", i.e., putting enough coffee that the top of the puck presses against the dispersion screen on lock-in, others will channel madly with the same treatment. I start with a few millimeters of clearance since that's what works best on most machines, then experiment from there.

That said, your results are gated by using preground coffee and a pressurized portafilter. Such a setup will not produce espresso comparable to even a mediocre cafe. Fresh coffee is a must, ideally 3-5 days post-roast. Best espresso gear on a student's budget? suggests grinders for around $200. The Feature Spotlight on Espresso Grinders covers the "last upgrade" level grinders that are about 2x more expensive.

November 6th, 2006, 11:53 am

HB wrote:That said, your results are gated by using preground coffee and a pressurized portafilter. Such a setup will not produce espresso comparable to even a mediocre cafe. Fresh coffee is a must, ideally 3-5 days post-roast. Best espresso gear on a student's budget? suggests grinders for around $200. The Feature Spotlight on Espresso Grinders covers the "last upgrade" level grinders that are about 2x more expensive.

wow... thanks for the info HB.
I was wondering what that plastic cap in my filter holder was, now i know!
I do indeed have a pressurized portafilter.... I feel terrible..... there i was (5 days ago), thinking i have found a good low-cost espresso machine with 15 bars of pressure. lol.

ok, glancing through the forums, gaggia seems like a popular low-cost option as an espresso machine.
how would i know if a machine operates on the basis of "pressurized portafilter"?

i'm looking at "Gaggia Cubika Coffee Maker" and "Delonghi EC730 Stainless Steel Espresso/Cappuccino Maker", and just can't tell if they use "pressurized portafilter" or not.

Shane

ps i'm still a student, so apart from the costs, it's the unstability of my location that prevents me from making a heavy investment and carrying a bulky coffee machine around.

#6: Post by HB » November 6th, 2006, 8:28 pm

I chuckle when reading boasts about "15 bars of pressure." That's about 6 bars higher than anyone would desire, unless they like bitter, overextracted swill. To add to the irony, it's not even true - 15 bars refers to the maximum pressure of the pump at no flow. With even the smallest flow, the pressure trails off dramatically (which is a good thing).

How to suss out the pressurized portafilters of the world? Generally speaking, entry level machines have them. It makes sense, since the marketing types figure some crema is better than nothing, and someone who buys an value-priced espresso machine is likely to spend even less on the grinder and coffee. "Better to have fake crema than no crema," they surely said to each other during the market launch.

A quick google for the Gelonghi EC730 reveals the usual market-speak: "Comes with two filter holders, a new 'never fail' crema filter holder for normal ground coffee, the other for the 'easy serving espresso' pods and free Illy pods." The Gaggia Cubika took only a few minutes to show its stripes: "Sistema Crema perfetta: Available." Easily recognized, even in Italian.

Below is the pressurized portafilter basket from the Krups XP4020:

I got this as a "thank you" gift for serving as a USBC judge. Other than taking it out for the above photo, it's been in storage in the attic. Before packing it away, I noted that a stock 14 gram Elektra Microcasa a Leva basket fit in the Krups, so there's hope. Oh, while researching your question, I ran across these photos:

First Series - Krups XP4020 Espresso Shots (photos courtesy Mark Prince and flickr)

Mark says "any machine, any grinder, any coffee" (photo courtesy Mark Prince and flickr)

He doesn't indicate whether this is with the stock basket or not. I believe he's researching for a CoffeeGeek review of the Krups XP4020, though I have no idea when it might be published.

#7: Post by **cannonfodder** » November 6th, 2006, 8:50 pm

I guess that could be without a pressurized portafilter but to develop that much crema, it is probably using the 'enhancer'. That or an all Robusta blend, but if Mark took the photos and pulled the shots I could not imagine him using the latter.

You could always get one of the new whiz bang Gaggia Achille lever.

November 7th, 2006, 5:10 pm

well, thanks for the advice guys.

i'm fascinated by the pictures (from krups XP4020), so i decided to take a research on that.
i realized, almost all espresso machines at my budget level have this "special crema" feature.... otherwise known as the pressurized portafilter operation.

this post (http://www.coffeegeek.com/forums/espres ... nes/198677) was a great help to me....
i have now taken action on returning the purchased morphy richards 47570 machine, and placed an order for krups XP4020 machine.
the gaggia carezza and espresso machines were good bit (around 40%) dearer than the krups XP4020, so i couldn't afford the jump.

but, i'll keep you guys posted on the results.
by the sounds of it Mark Prince was impressed by krups XP4020... and all USBC judges were given one... so must be worth it

(i'll be saving for a grinder soon)

#9: Post by HB » November 7th, 2006, 7:27 pm

jovial wrote:... and all USBC judges were given one... so must be worth it

The fact that Krups hosted the event may have also been part of the reason.

November 12th, 2006, 7:47 am

well guys.... I switched over to krups xp4020, and the immediate results are impressive.
managed to get 3mm of crema in my second espresso extraction from the machine.

taking the pros advice on-board, i also got myself a krups burr grinder

there's yet an espresso extraction issue which troubles me....
it, in fact, relates to this statement from HB.

HB wrote:I chuckle when reading boasts about "15 bars of pressure." That's about 6 bars higher than anyone would desire, unless they like bitter, overextracted swill. To add to the irony, it's not even true - 15 bars refers to the maximum pressure of the pump at no flow. With even the smallest flow, the pressure trails off dramatically (which is a good thing).

I read that you should ideally get an ounce of espresso in 15 to 25 seconds from the machine... i get that in 8 seconds!
I get slight bitterness and not alot of crema for that reason i believe.

i've tried tamping the coffee harder and using a finer grind coffee, but the end result of these two have led to water leakage from the side of the brew head....

i'm wondering is the espresso extraction time (in entry-level coffee machines) fixed?
in other words, maybe i am just given a fixed flow rate and i should attain the perfect brew by adjusting the coffee pack and the fineness of the grind.

as it is, i find it hard to control the flow of the water and hence the extraction time.
are there any other variables that i can play with?