In general, the goal of espresso blending differs from the goal of filter coffee blends (and some may argue that there are blends specific for French Press brewing or for serving with cream/milk). Drip coffees may be blended for complexity or for balance, but an espresso blend usually must be blended for balance or particular varietal qualities that would be favorable in a drip coffee might overwhelm the espresso extract.
Many espresso blends are based on one or several high quality Brazil arabicas, some washed, some dry-processed. They often involve some African coffees for winey acidity or enzymatic flowery /fruitiness, or a high grown Central American for a cleaner acidity.
Dry processed coffees can be responsible for the attractive crema on the cup, among other mechanical factors in the extraction process. Wet-processed Central Americans add positive aromatic qualities. Robustas, or coffea canephora, are used in cheaper blends, and some decent ones, to increase body and produce crema. They also add a particular bite to the cup. The notion that true "continental" espresso blends have Robusta? Nonsense! In fact the coffee samples from small Italian roasters I've had (in green form) appear to be very mild, sweet blends with about 40% Brazil Dry-process, 40% Colombian and 20%+ Centrals, like Guatemalan. For bite, syrupy or winey fruit, and earthiness you can use a DP Ethiopian. Its fun to play with Robusta but I personally don't like it too much beyond experimentation and I personally don't enjoy having more caffeine in my coffee than is necessary.
A Colombian-based espresso blend offers a sharper, sweeter flavor but won't result in as much crema production.
You can blend by the seat of your pants (not recommended) or make your process of establishing the coffees and the percentages logical. Start by developing the base, the backdrop in terms of flavor and a coffee that provides the kind of body, roast flavor and crema you like. I suggest Brazils, although any sweet coffee with mild acidity and texture in the mouthfeel are viable options.
Practice roasting this base coffee to different degrees of roast, and pulling straight shots of espresso. Get familiar with this cup and imagine what you would like to improve in it.
Do you want it to be sharper and sweeter, with more aromatics: perhaps you will want to add Central American coffees. Watch out with percentages above 25%, particularly if you like a lighter espresso roast. You will be losing some crema and body.
Do you want more body and sweetness: use a clean Indonesian like a Sulawesi or a premium Sumatra. You will be losing some brightness and at too light a roast level some of the earthy or herbal qualities can become sharper. You can go up to 50% with one of these and some are nice even at 100%, but if you are blending it with an other coffee that has more delicate features (such as floral wet processed Ethiopian) that you were hoping to highlight, I would not use too much of one of these coffees for risk of overwhelming them.
Do you want an earthy aggressive bite and more pungency: try a dry-processed Ethiopian. Some are brighter and more aromatic with fruitiness and wineyness. Some have great pungency in the darker roasts, and are fruitier in the lighter roasts. These produce great crema. I often enjoy straight shots of these coffees, but keep it to 25% or so in most blends.
Do you want spicy pungency: try a Yemeni coffee. These add wineyness too, and great crema. I keep this to 50% or less (normally 25% or so) in blends. SOme of the nicer ones have an aromatic sandalwood note that when balanced with the winey acidity produce really rich and exotic single origin espresso.
Do you want extreme bite: try an Aged coffee, a Monsooned coffee (Indian or better yet the Sulawesi Rantepao) or Robusta. Aged coffees and Monsooned add certain funky tastes that you may love, or perhaps hate. You just have to give them a try to find out but that is part of the fun. Robusta --- I would not go there unless you have too. I personally do not like the added caffeine they bring. They increase crema, but you also need to keep them below 20% in the blend, I personally never go above 15% with them.
|Arabica vs. Robusta? Arabica coffees (that means every coffee we sell except those at the very end of our list under the Premium Robusta heading) produce a fine crema, with good aromatics, and a lighter brown-yellow color. Robusta coffees (from the species coffea canefora) make a greater volume of crema, but it has larger "bubbles" and dissipates faster. Robusta has about 2x the caffeine of arabica, 2.2 to 2.4% compared to 1.1 to 1.3% in arabica. It can have a very rubbery-medicinal flavor when there is too much in the espresso blend. At a low percentage, 10% to 15%, it delivers a nice bite and it's negative features can be minimized.|
Perhaps you'll find that the coffee you chose for a base or even one of the accents are appealing to you as an espresso on their own. Single Origin Espresso is becoming more prevalent as people are experimenting with what an espresso can or should be. Thinking about espresso simply as a brewing method rather than a beverage in and of itself with predetermined parameters or "rules" to what it is made up of and what it should taste like can open up the door to a lot of non-traditional and sometimes exciting flavors in a shot. But there are definitely coffees that have too much of one quality or another that in an espresso extraction are not as enjoyable to me because that quality can become exaggerated.
There's a lot of ways to achieve great espresso. It's fun to experiment and I don't know if there is some terminal point where you achieve the perfect trans-subjective espresso.
Some Espresso Blends that I Like
I would recommend you try our Sweet Maria's Espresso Monkey Blend to see what you think. It will definitely give you a basis for comparison. We also create new espresso blends on a regular basis in our Espresso Workshop series. The Malabar Gold blend is a very exotic pre-blended espresso, and if that's what you like you might want to look into Aged coffees and Robustas for your own blends, and obviously you would want to be using Indian Monsooned Malabar. The Moka Kadir is a very fruity-winey North African and Yemen blend. So these three span the gamut of blends and can give youi a good idea what direction to take with your own blend. Many people also buy my Espresso Money blend and modify it by, for example, adding 15% robusta or adding 25% Aged coffee.
Here's a great starter blend for a sweeter, cleaner espresso. The absence of North African or Yemeni coffee takes out a little bite from the cup and possibly some lurking fruity flavor. this is, as noted above, a sweet blend used at a street level roasterie/caffe in Rome. They use a Guatemala Antigua for the Central:
or you could replace the Colombia with a premium Sumatra for more body and less brightness.
Some sharp sweetness (Central American) hides behind the nutty Brazil flavors and the wonderful Yemeni aromatics. Mandheling adds body and depth. Yemeni coffees are fun for espresso blends, where they can be used like spice to give zest the aromatically or enzymatically flat blends. Roast to Agtron 40 to 35. Good crema production from this blend due to the many dry-processed coffees
Ah, too sweet, too boring. You want something more aggressive, chocolatey? Drop the Centrals:
You can certainly keep going along this route by adding other coffees (monsooned, aged, robusta) to discover what they add and what they subtract from the blend.
For an potent Indian Monsooned-type blend you could do something like this:
For an potent Aged coffee blend you could do something like this:
(Aged Java is very potent and should probably not exceed 1/3 of the blend or so...)
Decaf Espresso? Low-caffeine espresso? That is why we stock the Brazil WP Decaf as a base. Use it as 50% of your blend to cut the caffeine in half, then add your main "character" coffees as usual. If you wanted an all-decaf blend you could try our own Sweet Maria's Decaf Espresso "Donkey" Blend ready to roast. We also are sending coffees that we select beforeheand to be decaffienated by water process and have been able to not only then source amazing components for an espresso blend in WP Decaf Ethiopias, Colombias, Centrals, and even Indonesian coffees, but also construct blends with complextiy, depth of character, loads of sweetness and syrupy fruited notes, and little to none of the flavor or scent of decaf coffee.