Miele CM6310 Countertop Coffee System review: Delicious automatic espresso -- if you're willing to put in the work
A cool two grand is a lot to spend on any kitchen gadget let alone a home espresso machine, but if you can justify the splurge, then strongly consider the $2,000 Miele CM6310 Countertop Coffee System (£1,299.00; AU$1,599). This coffeemaker creates the most flavorful espresso I've tasted from any superautomatic machine I've tested to date, including the more expensive Krups EA9010 ($2,500) and Philips Saeco GranBaristo Avanti ($3,000). The Miele CM6310 features a handy double-portion mode too, enabling it to prepare a pair of fancy coffee drinks with just one button press.
Like any advanced appliance though, the CM6310 isn't without some missteps. Most notably, its controls are often confusing, and its settings menus are painful to navigate. And despite its high price, the coffeemaker comes with a wobbly water tank constructed from thin, cheap-feeling plastic. Still, if you have the patience to tolerate its quirks, the Miele CM6310 rewards with mightily delicious espresso for hundreds less than its closest superautomatic competition.
Design and features
While the Miele CM6310 Countertop Coffee system will set you back quite a bit of cash, it does offer quite a bit of convenience. This machine is one of the few to qualify as what's called a superautomatic espresso maker. Essentially an appliance like this functions more akin to a robotic barista than a manual or semiautomatic espresso product, and is able to fashion complex cafe drinks from whole bean to steaming cup on its own.
Measuring 14 inches tall by 10 inches wide and reaching a depth of 17 inches, the Miele CM6310 occupies about as much counter space as two ordinary drip coffee makers stacked side by side. Still, the appliance shares an almost identical physical footprint as similar countertop espresso machines such as the Krups EA9010 and Philips Saeco GranBaristo Avanti. Also par for the espresso-maker course is the CM6310's box-like shape, tiny front-facing display clustered around a bank of buttons, twin coffee dispenser nozzles and a wide beverage drip tray below them.
Of course, the Krups EA9010 has a larger touchscreen and pairs it with a very logical, graphically driven user interface. The Miele CM6310's controls on the other hand are anything but intuitive. To the left of the machine's tiny LCD screen are four coffee cup icons meant to represent the most common beverages you'll likely order (espresso, coffee, cappuccino and latte macchiato).
Unfortunately, unlike the menus on the Krups appliance's color display or the GranBristo Avanti's physical keys, these symbols (and the buttons they indicate) are tiny and not labelled. As a result, I found it difficult to tell them apart at first -- or even divine their function -- until I consulted the manual or engaged in some trial and error.
Positioned on the left side of the display is a cursor pad to scroll through the Coffee System's menu screens. Running along the bottom edge of the control panel is a horizontal line of still more cryptic button symbols. Six in all, they control such functions as turning the machine on, view the complete library of drinks, tweak brewing details, and even create personal user profiles.
Though it eats up much of the appliance's left side, you access the CM6310's water tank from its top surface. The tank's plastic lid flips open and extends upward to function as a handle. Be careful though, because the lid and arms are extremely thin, can pop off their hinges easily, and honestly feel as though they might break at any moment. I also found that the tank's narrow base makes the container unstable (whether full or empty). Either at rest or when setting the tank onto a flat surface, the vessel will tip over if you're not mindful. In truth, the best removable water reservoir I've come across graces the semiautomatic Breville Barista Express. It's sturdy, a cinch to open and close, and has proper footing.
On top of the Miele CM6310 you'll find two hatches. One is a lid for the main bean hopper, while the other serves as a door for loading preground coffee into the machine. There's a cup warmer here, too; a rubbery pad meant for resting glasses and ceramic mugs. Miele claims the pad will heat coffee cups correctly in order to bring out maximum flavor from their contents.
One of the CM6310's defining features is its insulated stainless steel milk flask. Essentially a metal thermos, the 16.9-ounce container stands alone on the machine's right side and attaches to the main beverage dispenser via a clear, rubbery hose. It supplies dairy for cafe drinks or plain steamed milk. This convenience along with a spout for decanting hot water doesn't come cheap. As far as I can tell, these are the only two features not offered by the CM6310's less-expensive sibling, the $1,500 CM6110 model. Both appliances, however, can draw milk directly from grocery cartons with an included milk tube accessory.
I think the espresso machine's slickest trick is its double-portion mode, also available on the CM6310. Engaged by touching a button icon that vaguely resembles two cups placed in close proximity, when active the brewer will run any recipe from its drink library back to back. That means either two single or one double beverage is just a key tap away.
Aside from the textless buttons and shortcuts for popular drink types, you can access more of the brewer's recipes from within the "additional programs" menu. These include selections for shots of cafe lungo, cafe latte, plus hot or frothed milk.
Performance and taste
Even though the Miele CM6310 Countertop Coffee System certainly qualifies as a superautomatic espresso machine, there is a learning curve in terms of operating it correctly. Even after priming the appliance with a half-dozen espresso shots, the first espresso I pulled still tasted sour and under extracted.
Refractometer readings confirmed my suspicions -- I measured this liquid to have a TDS (total dissolved solids) percentage of 6 percent. Given the 0.4 ounce coffee dose which Miele claims the CM6310 uses per shot (default setting), this translates to an extraction percentage of 9.8 percent. The ideal extraction percentage for any brewed coffee is between 19 and 22 percent, but it only tells part of the story.
This percentage range typically indicates the likelihood that all of the flavor compounds which make java delicious have been pulled into solution, yet the unfavorable chemicals have remained behind within the grounds. I've found though that when the amount of grounds used is high compared with the volume of brewing water, as with espresso, the TDS figure the more important stat.
I also know from prior testing that my darkly roasted Costco Columbian test beans are capable of so much more taste, so I sifted through the CM6310's brewing settings for ways to improve the situation. Numerous espresso shots later, I found a few tweaks that coaxed the machine towards superb results. After dialing down the CM6310's integrated burr grinder to its second-finest coarseness level, I made sure the brew temperature was set to maximum.
Lastly I opted for "short" presoak time, which tells the gadget to wet its grounds momentarily before pumping water fully through the filter. Keep in mind that the Miele device forces you to change these parameters for each individual style of beverage the machine can make.
After wading through this tedium, I tasted some of the best espresso I've pulled from a home brewer. Deep, dark and rich, the espresso was remarkably full-bodied. The crema was a healthy shade of brown, too, with even a few spots of striping. The flavor was complex with chocolate, spice and hints of bright pear acidity, and it lingered pleasantly long on the palate.
logged average TDS percentages for these shots at a solid 7.4 percent, which translates to an extraction percentage of 9.23 percent. It may not sound high, but as I said before, TDS sometimes becomes the more telling analysis tool since it represents the actual amount of material suspended in a given coffee liquid.
Looking at TDS only this performance handily outclassed numbers I recorded from the Krups EA9010 (4.2 TDS) and Philips Saeco GranBaristo Avanti ( 4.7 TDS) when I tested them side by side with Miele's device (with identical beans from the same bag). Indeed, the only machine that fared better was the Breville Barista Express which not only produced shots with even more flavor depth but also clocked in with a higher average TDS percentage of 8.5 percent.
I admit the $2,000 CM6310 Miele Countertop Coffee System is a bit of mixed bag, which seems ridiculous for its price. Still, the espresso it makes can be so good that I still came away liking it. Sure it's a chore to program, tweak, and even fill with water, but as true espresso lovers will attest, quality is king and the CM6310 can deliver. It's also less expensive than competing superautomatic espresso makers that don't perform as well; namely the $2,500 Krups EA9010 and $3,000 Philips Saeco GranBaristo Avanti. That alone makes it easy to recommend Miele's countertop brewer.
Another option, which seems like a sweeter deal, is Miele's step-down device, the $1,500 CM6110 model. If it has the same espresso-making engine and milk-frothing ability (from cartons) under the hood as the CM6310, then I'd gladly make the swap for $500 more in my pocket. For those who prefer a manual approach, there's currently no better combination of price, performance and simplicity than the Breville Barista Express.