Those of us who have been involved in any sort of project ( anyone renovated their house? ) would know about the iron law of triangle optimization: you can only have two of the following three: Cost, Quality, Time. I find the same applies to espresso machines too - you can only have two of these three: Machine Cost, Beverage Quality, Ease of Use. A semi-auto machine can be had at a reasonable price and can produce excellent shots, but can be fussy to operate. An average superauto will be high in Ease of Use ( just press! ) and can be pretty affordable, but can only produce passable shots. High end commercial superautos can produce decent shots at a press of the button, but would be priced beyond the regular home coffee enthusiast.
So when I did some preliminary pre-review searching on the net about the Mypressi Twist, some writeups ( eg:http://tinyurl.com/yjaphf5
) indicated that this device may bend the "iron law" a little. Interest perked, Cheah and I decided to spend a little more time to look into this device in detail. We did general tasting, blind comparative tasting with "instrumented" shots and temperature measurements with different preheating methods ( more on importance of preheating later ). We'll give the device some ratings at the end of the article, but for some more detail, read on...
Theory of Operation
The mypressi twist is a handheld espresso extraction device - I hesistate to call it an espresso machine as it's pretty radically different. It does not heat the brewing water - you need to fill its water chamber with the required amount of near-boiling water before you pull a shot. It does not depend on a pump to provide the 9 bars of pressure needed for extraction - it utilises compressed NO2 or CO2 cartridges. Gas from the cartridge is regulated to 9 bars and pushes the filled water through the coffee puck to extract espresso. You don't press a button to start/stop the shot, instead you pull a trigger and hold it down till the shot is done - kinda like helping yourself at a soda fountain in 7-Eleven. This makes the device portable due to its size and not needing an electricity supply to operate. There is beauty in this simplicity which makes is a very temperature stable during brewing - more on this in the measurements section. Bottom line - does this device delivery drinkable shots? More than...General Tasting and Impressions
Cheah and I got to familiarise ourselves with the machine at a drinking session in Coffee Ritual, with Chin and Ee Mei also giving comments on the shots. We used a five day old bag of Yellow Bird espresso blend from Oriole roasters in Singapore. We ground the coffee with a Mazzer Major. We stuck with a dose of 18gms ( "advice" from James Hoffman's Mypressi review ) and adjusted the Major to give us an approx 40ml shot in 30 seconds. It was pretty easy to adjust the grind - zero'd in after the third shot and rest of the pulls were consistent. Shout out for Chin's 53mm tamper ( same basket size as Coffee Ritual's La San Marco machine). We could see very balanced flow from the "bottomless" basket with tiger stripes throughout extraction. The resulting espressos were very good - balanced, complex and medium bodied. The shots were pretty - lots of tiger skin in the crema. Just for fun we also tried Cheah's Skerton - we found a decent grind setting after two blocked shots and one gusher ( the Skerton's grind setting steps were huge for espresso ). However, after the correct setting was found, the shot came out nicely too and tasted good too. So far, so good - so we decided to measure the extraction of the device and also compare it with a good commercial machine using a known coffee...Blind Tasting
We did a blind tasting session at Departure Lounge to compare the Mypressi with the resident Expobar three group machine. This machine is a E61 group machine with individual PID ( set to 94deg ) controlled brew boiler for each group. In other words, a machine which will pull consistently good shots - the Twist will have to punch well above its weight to compete... We used seven day old Departure Lounge House Blend ( roasted by Five Senses ). We found that by grinding with DL's Mazzer Kony at its standard setting the Mypressi pulled shots in the 30 second range too, so we stayed with the grinder settings for the whole test. We carefully weighed the grounds and shots, and measured the extraction with a Mojo Espresso refractometer ( see other post for readings ). I pulled the shots on the Twist and Loo pulled on the Expobar, using identical demitasses. Loo and Cheah did the tasting. First up was shots using "steaming" preheating of the mypressi. Both judges agreed that the shots were good and very close in taste - to the degree that is would be difficult to tell apart if not tasted back to back. There was an agreed slight complexity edge in favour of the Expobar. The next pair of shots were done with the "soaking" preheating of the Twist. Again, the shots were very very close. We decided to stop the comparison testing at this point as is was clear that further results would not show any real preference. We then dailled in Cheah's Skerton, which produced a similar tasting shot on the Mypressi but with reduced body.Conclusions
We were pretty impressed with the results we could obtain with this machine. The shots weren't compromised when compared with a well reputed machine helmed by an experienced barista - in fact we could hardly taste the difference. The measured extraction results indicated that the machine performed very similarly to the PID'ed E61 group machine. Brew temperature was correct for brewing ( with a simple preheating step ) and very stable throughout the extraction ( see test results in next post ). The extraction flow looked very nice and had minimal squirting ( if at all ), indicating tolerance to imperfect distribution/tamping.
As a way to get espresso when travelling or on holiday, this is an excellent solution when coupled with a Skerton hand grinder. You might even keep one in your drawer in the office and pull shots in the pantry - maybe convert a colleague to two to real espresso:)
For home use, it makes a very good alternative to an entry level single boiler machine. It does require an extra preheating step but is way more temperature stable - less "sink shots". However, if you enjoy milk based drinks then a solution would be needed for steaming the milk. If you already have an entry level single boiler machine, then the Mypressi is an excellent addition - use the Mypressi to pull the shots and the machine to steam the milk ( also preheat the mypressi with the machine's steam wand ).
The cartridges ( standard food service industry item used in cream whippers ) are fairly priced and can pull four to five double shots each - you will need to come out with a system to remind yourself how many shot you have pulled so as not to, er, run out of gas, half way through a shot.
If you like your shots straight, or if you are dipping your toes into the world of espresso, this device certainly skews the value triangle a fair amount.
Crucial to good espresso is freshly ground fresh beans - there's lots of advice in the forum about suitable grinders and sources of beans. Stay away from pre-ground!Rating ( out of five )
Espresso Quality - 4.5
Ease of Use - 3
Value for Money - 4.5
Details of technical tests during the review http://coffeeloversmalaysia.com/index.php?topic=557.0
Review unit courtesy of www.cuppa.com.my