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The Big Two Espresso Cheapskate Coffee
Espresso
I've tried to cram a bunch of information onto this page. Espresso is complicated and I could probably spout off useless tidbits for a week. My hope is that this section will be used as a reference or as a starting point.
Espresso is generally regarded as the highest form of coffee. Though the definition of espresso is simple, the process of making a good espresso shot is very complex. Simply put, espresso is coffee brewed under pressure. Now, let's look at how we go about making a decent shot.
Why Espresso?
Espresso coffee is by far the most complex type of coffee to prepare and the equipment needed is FAR more expensive than almost any other type of coffee brewing equipment. So, why spend so much time and effort on espresso?
Espresso is brewed under extreme pressure. This pressure actually forces dissolved oils out of the ground coffee beans. These oils carry flavors from the beans that, with other (non-pressurized) brew methods, are left behind. There is a big difference between espresso and strong coffee (keep this in mind as you read on -- I'll give an example of how an espresso machine can make strong coffee instead of espresso).
But still, "Why Espresso?" It just tastes so good, that's why.
How to Drink Espresso
There are several ways that you can enjoy your espresso. I'll go over them in order of size.
Straight Espresso
Lots of coffee places in the States that serve "espresso" really have no idea what they are doing. It is common for an espresso shot to be served as a cup of coffee of about 4 or 5 ounces. Those big old shots usually take about 10 seconds to extract. Remember how I said espresso uses the pressure of the machine to extract tasty oils and put them in your cup? Think a great big shot pulled in 10 seconds ever got a chance to build up that pressure? Nope. What you've just been served is a cup of strong coffee made on a machine costing thousands of dollars that could have been prepared using a stove-top moka pot that would set you back about $30. Beware of bad espresso. But...then there's good espresso...
This is a personal favorite of mine. Get that shot ready, put it in a cup and drink it up. Simple as that. Usually about three swigs or sips of espresso per serving. This is coffee at its most exposed. Every flaw in your preparation technique, every flaw in the roasting process and every flaw in the beans themselves are just hanging out there for the tasting. Of course, where there's evil, there's always good. If you started with quality beans that were properly roasted and you nail that preparation, there's nothing that compares in the coffee world. When all these things come together, it's sometimes referred to as a "God Shot". A skilled barista can consistently pull dozens of tasty, high quality espressos back to back, but may only get that "God Shot" once out of every hundred or more attempts.
Espresso with Milk
Before getting too far into this, I'd like to point out that there's not much coffee etiquette in the US. Not so in Europe, and especially in Italy. In Italy, you can drink coffee all day long. It's expected, they're pretty great at making coffee and everyone loves it. Now, if you want milk in your coffee (a macchiato, cappuccino, or latte), you'd better get up early because putting milk in your coffee after 10 am in Italy is like ordering liquor before noon in an American restaurant. You'll get what you asked for, but you'll get a funny look or two.
Espresso Macchiato
Contrary to what "Big Coffee" wants you to believe, a macchiato is not a milkshake with some espresso in it, whipped cream on top and caramel sauce drizzled all over. While this may be tasty, it's really more at home in Baskin Robbins than a coffee joint. Drink one of these daily and you'd better save up for a new pair of big pants.
No, the word macchiato means "marked" in Italian. That's just what it is in coffee too. Usually served in an espresso cup or special macchiato cup (just slightly bigger), the shot is pulled into the cup, a small amount of milk is steamed and that frothy steamed milk is poured into the shot to mark it. Assuming you pulled a shot of about 1 to 1.5 ounces, you'd usually add about another ounce or even less of steamed milk.
I'm a big fan of the macchiato. There's not so much milk as to dilute the taste of the espresso that you just obsessed about creating, but the milk brings out much of the sweetness of the espresso and you'll often taste things in a macchiato that you cannot taste as easily in a straight shot. There's much less bitterness and the overall taste is much smoother (as you'd expect).
Cappuccino
Now, here's a popular drink the world 'round. The cappuccino is a drink made in thirds. It contains one third espresso, one third steamed milk, and one third frothed milk foam. A double shot of espresso is usually about 1.5 to 2 ounces (sometimes less if it's ristretto). Therefore, the total volume of the cappuccino should be from 4.5 to 6 ounces. A capp of this size is usually referred to as a "traditional" capp.
The espresso is pulled into a small cup and the milk is added on top of the espresso. If steamed properly, the barista will have stretched the milk to the point that the steamed milk and the foam on top of that milk are barely distinguishable. The froth should be what is called microfoam. Microfoam is milk that has had air introduced into it in such small quantities that the bubbles are extremely fine. The way to tell if you have achieved microfoam is to look at the milk's surface. There should be no visible bubbles and the surface should look very shiny -- it's often referred to as liquid chrome. As the milk is poured, both the steamed milk and the microfoam should pour from the pitcher at the same time. It should not be necessary to use a spoon to hold back the foam just to be spooned on top after pouring the milk.
The common mistakes seen when making a cappuccino usually involve the quality of the milk after it has been steamed. There should never be large visible bubbles. The foam should not be stiff and hold its shape on the top of the drink, rather it should be silky and smooth. A capp should never resemble a cup full of dish soap bubbles.
Most coffee places offer cappuccinos in sizes that you would see at a soda fountain. I often see a small capp as a 12 ounce size, medium at 16 ounces, and large at 20 ounces. Do you think they add more coffee to your 20 ounce "cappuccino"? Heck no. What you're getting is 18 ounces of steamed milk and a shot of espresso. The American mantra of "more is better" does not apply.
If you want to taste the espresso in a cappuccino (why else would you even order one?) ask the barista to make it about 6 ounces. Tell him to use less milk. You're paying the same as you would for a small and the shop is using less milk, so they shouldn't mind. Of course, if you're in a place that sells 20 ounce "cappuccinos", there's a good chance that the espresso that they're using to build that drink is nasty in the first place and they're using all that milk to cover up the taste. Oh, there's no chocolate or cinnamon on top of a cappuccino either.
When in a good shop, you can usually just order a "traditional cappuccino" and get the real deal. Give it a shot next time you're over at my house or at Intelligentsia or Vivace. You'll like it.
Latte or Cafe Latte
The latte is very much like the cappuccino, with only a couple of small differences. It begins with a shot of espresso, just like a macchiato or capp, but the milk is steamed just a bit differently. With a cappuccino, you introduce more air into the milk to get that third of frothy foam. When making a latte, you introduce some air, but not as much and then simply heat and stir the milk by lowering the wand toward the bottom of the pitcher until reaching a temperature of about 140F (just barely too hot to hold with your hand on the outside of the pitcher). The proper size of a latte is about 8 to 12 ounces.
Just like with a cappuccino, you may have options for 16 or 20 ounces at the local coffee joint. With a latte, you can skip the special instructions and simply order a small (usually 12 ounces) and get a drink of about the right proportions.
"Espresso Coffee"
There are many misconceptions about espresso, most likely because of "big coffee's" marketing. I've heard the term "espresso coffee" used by coffee newbies (nothing wrong with that) and professional roasters alike.
The first and biggest misconception about coffee used for making espresso is that the coffee needs to be roasted extremely dark, often to the point where the coffee oils coat the surface of the roasted bean. This is not true. Some of the most highly regarded espresso blends contain coffees that are not roasted darkly at all.
Coffee for making espresso may or may not:
be roasted specifically for espresso.
be a blend of different coffees.
come from just one coffee lot.
be roasted dark or light or in between.
be the same lot of coffee roasted to different levels then blended.
What I'm saying here is that there are no rules about which type of coffee to use to make espresso, it's just that some coffees work better than others. Much of this also depends on the type of espresso machine you're using and how well you're able to control all of the variables involved in the espresso making process.
Espresso blends are generally more tolerant to variations in temperature. One bean in a blend may not particularly like the brew temperature of a shot, but that may be covered up by another bean in the blend for which that particular temperature is optimum.
Single origin coffee (coffee from a single lot) may or may not make a good espresso. One thing for sure is that single origins are very temperature sensitive. The flavor of the coffee may change dramatically simply by changing the brew temperature by a degree or two.
So, while most espresso is made from purpose-roasted espresso blends, these types are not necessary to make an excellent cup. The only way to tell is to experiment and taste everything you can to find what you like.
Pressure
How much pressure? Generally, espresso is brewed in a purpose-built espresso machine capable of achieving approximately 9 bars of pressure (that's about 130 psi). This is a lot of pressure and the only machines that are capable of achieving this pressure are ones that use either a manual lever or an electric pump.
Lever Espresso Machines
Older (or newer nostalgic) espresso machines use a lever to build up pressure using the mechanical advantage of the lever, plus the pulling action of the barista. Because lever machines are only as consistent as the person using them, they require a good deal of skill and may provide vastly different results when used by different baristas.
Pump Espresso Machines
Most modern machines (other than those popular throwback lever machines that still have a loyal following) use a pump to build up pressure for creating the espresso. Not only is the pump easier to use (flip a switch, move a lever, push a button), but it's much more consistent and usually adjustments to the pump pressure can be made to easily tweak the espresso-making process.
There Must Be More To It!
Of course, the pressure that defines the espresso-making process is just one part of the equation. To make a good espresso, you need the correct amount of coffee and the coffee needs to be properly ground and prepared. The process of preparing the coffee is often referred to as "grind, dose, and distribution" or GDD. The last part of the process is making sure the water you're using is heated to the proper temperature.
How much coffee?
The amount of coffee you use to make espresso varies (seems like everything is a variable? well, it is -- that's what makes this so tough). Let's start with the single shot versus the double shot. This seems to be an area of confusion, even among folks who work at coffee joints.
The Single Shot Of Espresso
A single shot of espresso, in its pure form is a relatively rare thing. To make a single shot of espresso, you would use a single shot filter basket and anywhere from 6 to 10 grams (0.21 to 0.35 ounces) of ground coffee. The resulting shot of espresso is about 20 to 30 ml (0.75 to 1 fluid ounce).
Because most American coffee joints use double baskets exclusively, if you order a single shot, what you'll usually get is half of a double shot. The spouts of the portafilter split the shot in two and they serve you what comes out of one of the spouts instead of both. This is why a true single shot is pretty rare in the US.
The Double Shot Of Espresso
A double espresso shot is the most common type found in the US. Reasons for serving doubles are pretty obvious from a business standpoint. Americans want more, and a double shot is bigger than a single shot. Double shots tend to have more room for error than single shots, thereby producing more consistent quality. A double shot uses a double filter basket (like the one in the photo in the glossary). The amount of coffee used is from 14 to 20 grams (0.5 to 0.7 ounces) and the volume of the shot produced varies from 1 ounce (30 ml) for a ristretto or "restricted" shot to 2 ounces (60 ml).
How Do The Big Two Fit In?
If you have read this site in order from left to right (who does that?), you may have already read the section I call The Big Two. In this section, I talk about coffee freshness and the grinder. When preparing espresso, this is one area where you cannot cheap out.
Coffee Freshness
I'll go over this again, as it's essential to making good espresso and the rules are a little different when you're using coffee for espresso.
After coffee is roasted, it degasses CO2 for about two to four days. It depends on the coffee and it depends on how it was roasted. During this period (you'll have to try to figure out what this period is for the coffee you've chosen), you probably don't want to use the coffee. Just let it rest. If you make espresso with coffee that's not properly rested, it will sometimes taste a little like baking soda. If you get that taste, try again in a day.
On the other end of the equation, espresso making is very intolerant to coffee that's too old. Again, depending on the type of beans that you're using, the coffee may last for two weeks or up to four weeks (four weeks is a LONG time). As the coffee begins to stale, you'll notice a decline in the amount of crema (that's the lighter colored foam that sits on top of a properly pulled espresso shot). The coffee will taste flat and making a good shot will become much more difficult. Stale coffee increases the chances of channeling and makes the espresso preparation process extremely frustrating.
"Best Before" dates on bags of coffee in the grocery store (or at your local "big coffee" shop) tell you nothing. The latest trick that "big coffee" is using is to put a "bag filled on date". I've also seen this in fancy upscale grocery stores ("bin filled on date"). Unless you roast your own coffee, order from a "roast to order" joint (there are tons of these places that are really good and can be found all over the internet), or get your coffee from a local roaster who you can talk to, assume the coffee is not fresh. Also, don't fall for "this coffee is the best in Italy" hype. In Italy, this coffee may be the best, but consider how far the coffee needs to travel to get into your grubby little hands. I plan to try all the big Italian brands when I'm in Europe, but I'm not wasting my time/money on stale beans.
So, order from a "roast to order" joint on the web, go talk to you local roaster and ask what the roast date is, or only buy coffee that has a "roasted on" date on the bag. Those are your best bets.
Grinder
The grinder is the number one, most important piece of espresso making equipment. If you look around on the internet at various coffee sites, you're likely to see that most serious coffee people agree that you can make better espresso with a $500 grinder and a $200 espresso machine than you can with a $200 grinder and a $2,000 espresso machine.
When choosing a grinder for espresso, the most important features are grind consistency and adjustability.
A grinder that is consistent produces ground coffee of approximately uniform particle size. There's nothing you can do to control this other than to purchase a good, consistent grinder. Many companies make grinders consistent enough to make espresso, but some of the best are made by Mazzer, Macap, and Cimbali (Chris Coffee is a great source for grinders, but the good ones don't come cheap).
To make espresso, you need to be able to adjust the grinder in very fine increments. All other things being equal, more finely ground coffee will produce less coffee in a given time than a coarser grind. the more finely packed in coffee particles create a greater resistance against the pressurized water being forced through the coffee puck by your espresso machine.
This should be your goal -- all other things being equal, that is. Once you've made a bunch of espresso shots (like hundreds, or even thousands), your routine needs to be such that you can reasonably use the same amount of coffee, properly distribute the coffee in the basket, tamp the coffee with the same amount of pressure every time and make your machine provide the same pressure and temperature from shot to shot. Once you've done this, the only thing you need to change to adjust or "dial in" your espresso is the fineness or coarseness of the grind.
Most espresso-making people agree that the best type of grind adjustment for an espresso grinder is a stepless or infinitely adjustable grinder. If you've got that routine down like I talked about above, making very, very fine grind adjustments will allow you to get just the right amount of espresso in your target time (25 to 30 seconds).
Brew Temperature
The temperature at which you brew your espresso can make a big difference in the final taste. Different espresso machines have different capabilities as far as temperature stability, adjustability and repeatability from shot to shot. These capabilities may be solely based on barista technique, on the machine's design or, most often, a combination of design and technique.
As a general rule, the larger the espresso machine, the more thermally stable it will be. In addition to size, there are several design factors that weigh into the temp stability of your machine. Machines have boilers (either one or two) inside them that are heated to a predetermined temperature based on their intended use (brewing espresso or steaming milk).
Single Boiler Espresso Machines
The simplest machine is of the single boiler design. These machines are usually only sold as consumer machines.
Because you want to brew your espresso at a much lower temperature than you need for steaming milk, a single boiler machine generally has two modes: brew and steam. The upside to this design is that it's less expensive to manufacture a single boiler machine. The downside is that it takes several minutes for the temperature to change from brew mode to steam mode. This makes it extremely difficult to make back to back drinks that involve the steaming of milk.
The most popular single boiler machine ever made is the Rancilio Silvia. This is a popular machine because of its attractive price point and the very high quality espresso that it is capable of brewing (with some practice). The company Gaggia makes some very capable single boiler machines at a lower price point.
Double / Dual / Twin Boiler Espresso Machines
Some machines have one brew boiler and separate steam boiler. They go by the many names listed above.
The steam boiler super-heats the water above boiling to supply steam for steaming milk for cappuccinos, lattes and macchiatos. This steam boiler also supplies hot water (steam is drawn from the top of the boiler, hot water is drawn from the bottom) for making tea or americanos (more on that later). Because twin boiler machines have purpose-built boilers, it's possible to brew espresso and steam milk at the same time. Many, but not all, commercial espresso machines are dual boiler. The two most highly regarded dual-boiler manufacturers are La Marzocco and Synesso. There are also several consumer (or pro-sumer -- look at the prices) double boiler machines out there and they're becoming much more popular in the home market (this is what I use at home).
Heat Exchanger or HX Espresso Machines
HX machines have one single boiler that maintains a high temperature (above boiling) to produce steam and hot water. There is a heat exchange mechanism through which the water passes on its way to the coffee that lowers the temperature to the proper level for brewing espresso. HX machines are able to produce extremely consistent results in the hands of a skilled barista, but they have a steep learning curve compared to a double or single boiler machine. There is an outstanding article on how to use an HX machine on Home-Barista.com. Heat exchanger machines are very commonly found in cafes, as you can steam and brew at the same time and they offer a good deal of thermal stability.
Of the three main varieties of espresso machines, the simplest to use is the twin boiler, the most difficult is the heat exchanger.
The Machine's Temperature Management
But wait, there's more. How do the boilers on these machines know the water temperature and how do they maintain them? More importantly: to what degree of precision do they maintain that temperature?
Temperature in a boiler is sensed either by a temperature probe (makes sense) or a pressure probe. If you remember Boyles law from high school physics, temperature, pressure and volume are all related. Well, we have a fixed volume (the boiler size), so now we have a direct relationship between temperature and pressure. The higher the temperature, the higher the pressure. Pretty simple, right? That Boyle guy was pretty smart.
Now that we've got a way to read the temperature (or pressure) of a boiler, we need a way to maintain a target temp. The boiler is heated using a heating element (like the one on your electric stove, but different). Left on all the time, that heating element will super-heat your water and over-pressurize your boiler to the point where it explodes (did you see that Mythbusters where they exploded a full-sized water heater -- imagine that on a smaller scale on your kitchen counter). So, when the temperature in the boiler reaches a particular value, the temperature (or pressure) sensor tells the heating element to turn off. When the water cools to a lower preset value, the element turns on again. So, if you have a machine with 5 degrees Celsius between on and off, you have what is called a 5 degree "deadband". In this deadband, you can either guess the temperature of the water coming out of the brew head or you can learn the behavior of your machine and vary your technique to get the desired result. Or...
...Or you could go out and get yourself a PID (that's Proportional Integrated Derivative) control and install that sucker on your machine (some high-end machines come with this already). The PID is a fancy thermostat with a very, very small deadband (usually less than one degree C or even less than one degree F) with a digital controller that allows you to adjust your brew temperature simply by pushing a few buttons. That's the good stuff.
OK, that's probably WAY too much information, but if you're planning on purchasing a machine, do some research and find out how that machine manages the temperature and what you'll need to do to get consistent results.
What to do with the Temperature
Now that we've talked about the basics (this will get much more in-depth for your particular machine) of how temperature is controlled, who cares in the first place?
The answer is: you...you (nod knowingly).
If you pull a shot of espresso and it tastes sour, it's probably because of temperature that's too low. Try again using a higher temp.
If you pull a shot and it tastes bitter, it's probably because of the temp being too high. Cool it off a couple of degrees and try again.
Once you find the good temp for a given blend (and this may change as the blend ages over the weeks you're drinking it) take note and use the same profile the next time.