Making quality espresso is both an art and a science. It requires great care and consciousness on the part of the operator.
When purchasing an espresso machine, look for temperature capabilities around 195-204 degrees Fahrenheit, and pressure capabilities close to 135 psi. For great tasting espresso, use 100% Arabica coffees, roasted for espresso.
Espresso requires finely ground coffee that is brewed at the proper temperature and pressure to extract only the finest qualities of the coffee bean.
According to the Specialty Coffee Association of America, a single shot of espresso uses 7g to 9g of finely ground coffee extracted with water under 135psi (9 bars) of pressure at a temperature of 198º to 202ºF (92º to 95ºC) over a period of 20 to 30 seconds, counted from the time the brew button is activated, to a volume of .75 oz. to 1 oz. (22ml to 30ml).
Pulling an Espresso Shot
Begin with a preheated cup
If espresso is brewed into a cold cup or shot glass the rapid drop in temperature will alter the espresso, resulting in a bitter tasting shot. Whenever possible, pull shots into the vessel they will be served in, otherwise use a shot glass.
Rinse, Clean and Dry Portafilter Basket
There are two reasons to rinse clean and dry the portafilter basket. First, we do not want to re-extract old coffee grounds. Second, we do not want to wet the freshly ground coffee. Water is more likely to travel where water already is. If the coffee gets wet, water will find the path of least resistance and over-extract the already wet areas of the puck. This is called channeling.
Grind only as much coffee as you need to fill the portafilter basket. Familiarize yourself with the time it takes to grind the coffee you need. Every grinder is a little different; try to keep waste to a minimum.
Gently pull the dosing lever until the basket is just a little more than full.
The purpose of leveling is to evenly distribute the ground coffee in the portafilter. There are many ways to achieve this. Some things to keep in mind:
· Ensure coffee is evenly distributed against the edge of the basket before sweeping off excess grounds.
· Avoid pressing down or pre-packing.
· Be aware of the contours of your fingers. Try to create an even, horizontal surface, avoiding pits or mounds.
· One way to limit waste is to level the excess grounds into the dosing chamber of the grinder. Avoid letting the spouts of the portafilter drip water into the dosing chamber.
· Place the portafilter on a packing mat or use a computer mouse pad. The angle of the portafilter handle is designed so that the basket will be horizontal if the spouts and handle are resting evenly on the mat.
· Set the tamper in the basket to ensure a horizontal tamp. Place the tamper on the horizontally leveled grounds and tamp lightly. Gently tap the front of the portafilter with the handle of the tamper to knock loose any grounds resting on the inside edge of the basket.
· Now tamp by evenly distributing 30 to 40 pounds of pressure, holding the tamper as if you were shaking someone’s hand. Position your thumb and forefinger on the base of the tamper for balance and stability. To avoid strain, keep your elbow at a right angle and your wrist aligned vertically with your forearm. Do not tamp with your palm as this makes it difficult to maintain stability and will strain your wrist. If you do not know what 30 to 40 pounds of pressure feels like, practice tamping on a bathroom scale.
Flush Group Head
Before you insert the portafilter into the group head, run water through the group head for 3 to 5 seconds. This helps clean the dispersion screen and allows for greater temperature consistency by pushing out water near the head of the group that has cooled.
Clean Portafilter Spouts
Sometimes coffee grounds can stick to the spouts of the portafilter and make their way into the cup. This makes for a gritty, unpleasant mouth feel. To prevent this, keep your packing mat clean and rinse the portafilter spouts while you preheat and flush the group head.
Insert Portafilter into Group Head and Brew
Be careful not to jostle the portafilter when you insert it into the group head. Press the brew switch immediately. The ground coffee will scorch if it is allowed to sit in the hot group head.
Observe the Pour
Each shot of espresso should be .75 oz. to 1 oz., including crema. It is extracted over a period of 20-30 seconds, counted from the time the brew switch is activated. It should begin pouring dark brown and slowly brighten, turning blond in the last few seconds. Watch out for light “candy cane” stripes in the flow. These stripes are a sign of inconsistent extraction. Once brewed, the surface of the espresso should be reddish brown with dark brown flecks. These flecks are small fragments of the cell walls of the coffee bean that have made it through the filter and are responsible for much of the pleasant flavors in espresso.
Serve Shots Immediately
The espresso will cool and the crema will fade, so serve or use your shots immediately.
Sight: Look at the surface of the espresso (aka the crema or foam). It should be rich and unbroken and its color should be reddish brown with dark brown flecks.
Smell: As you lift the demitasse of freshly brewed espresso, inhale deeply. The aroma will instantly awaken your palate. Does it smell sweet, chocolaty, sour, sharp, and/or fruity? Your nose will give you a clue to what is in store for your tongue. Coffee is an organoleptic experience, requiring smell and taste to fully experience what’s in the cup.
Feel: As you drink the espresso, start evaluating it by determining the basics. Decide whether the liquid is lying pleasantly on your tongue. Press the liquid against the roof of your mouth. Is the feeling thin or thick? This is how we determine body. Now you can begin to evaluate taste and aftertaste.
Taste: The human tongue and mouth are comprised of taste buds dedicated to detecting particular flavors. The tip of your tongue is responsible for detecting sweet and sometimes salt, the sides sour, the top and front sweet, and the back tastes bitter flavors. It is important to be able to identify and not confuse the flavors you taste. Determining which taste buds are stimulated when the drink covers the tongue can help you isolate the tastes that you experience.
A Good Espresso
A properly brewed shot of espresso should be rich and heavy in body. The coffee should have an initial impression of intensity. Depending upon your personal sensitivity, you may detect concentrated bittersweet cocoa or bright acidity. Do you taste the coffee heavier on the tip and the top of your tongue? This is where the espresso should perform best. Those are your sweet sensors. So while the coffee may not taste as if sugar has been added, if it lies heavily on these parts of the tongue, you are sensing a level of sweetness.
Does the coffee stimulate the sides of your tongue? Do you feel it hit the back bitter sensor; does that intensity dominate the overall flavor? If the sides or the back of your tongue are “more excited” than the tip or the top, you’ll need to evaluate it. Does that taste add or detract from the overall impression of the coffee?
Aftertaste is one of the most important attributes of a good shot of espresso. The tiny bubbles of the crema act as the flavors’ time-release capsules. You may now detect cocoa, caramel, fruit, or floral notes on your tongue after you’ve swallowed. Use your sense of touch again. Does the shot leave an oily film on your tongue? Is the texture rough and drying or smooth and long lasting? Which taste buds are stimulated even after the coffee is gone?
Keeping your espresso machine and grinder in shape:
Remove portafilter, knock out puck, rinse and reinsert portafilter.
When time permits, keep your portafilter clean. Always keep the portafilter in the group head when it is not in use. This will keep it hot when the machine is turned on. If it is allowed to cool, the portafilter will drop the temperature of the brew water when espresso is brewed, causing the espresso to be thin and under-extracted.
Adjusting the Grind
The grinder needs frequent adjustment to properly do its job. The grind size needs to be right in order to achieve a proper extraction. Temperature, humidity, pressure, and roast date are examples of factors that can affect the way the coffee behaves once ground.
Coffee that is ground too fine will pack tightly together, not allowing water to pass through it easily. This causes over-extraction, where the water is in contact with the coffee for more than the optimum time, resulting in a bitter or burnt taste. Grind that is too coarse allows water to pass through too fast resulting in a brew that is weak and thin in body because the coffee was not exposed to the water long enough.
When you have developed a consistent dosing, leveling and tamping technique and you notice the espresso is not pouring properly, it is time to adjust the grind. Make small adjustments, one or two notches at a time. As a general rule, each notch on the adjustment collar represents about 2 to 4 seconds of brew time. After moving the adjustment collar, be sure to grind for at least 3 seconds and discard the coffee. Otherwise, coffee at the old grind setting will be in the grinding chamber and chute, and the next set of shots will not reflect the adjusted grind.
Steamed milk is an ideal medium for presenting espresso to the palette. It tones down bitterness and acidity without masking the pleasant flavors espresso has to offer. Steaming milk is just as delicate a process as preparing espresso. Care must be taken by the barista to create a drink that is the right temperature and texture. Experiencing an espresso beverage prepared with steamed milk is as much about feel as it is about taste.
Use cold milk and a clean, cold pitcher.
When you use cold milk and a clean, cold pitcher it takes a little more time to heat the milk. This means you will have more time to roll the infused air, breaking up the air bubbles, and creating smooth, velvety foam. When pouring your milk, only use as much as you need for the drink. Avoid milk waste. Keep in mind that heating the milk will cause it to expand. Foam, espresso and flavoring (if any) will add volume as well. Never re-steam milk. Sugars in the milk begin to break down when milk is heated, and re-steamed milk will taste flat or bland.
Purge steam wand
Turn on the steam wand and leave it on for a few seconds. Purging the steam wand before you begin steaming will flush out water condensation built up inside the steam wand.
Lower the steam wand tip just below the surface of the milk.
The steam wand should be placed at about a 45-degree angle, and submerged about a half inch below the surface of the milk, just right (or left) of center. This will help create a whirlpool. A whirlpool is the most effective way to roll the infused air and create micro-fine bubbles.
Turn on the steam wand.
Open the steam valve and introduce steam into the milk. Open the valve enough to ensure full steam pressure.
Create a whirlpool and gently introduce air into the milk.
With the tip of the wand just below the surface of the milk and off to the right, angle the pitcher so as to create a gentle whirlpool. Lower the pitcher so that the holes at the tip of the wand are just barely exposed at the surface of the milk. Introduce a small amount of air into the milk. This is often called “stretching.” The longer you stretch the more foam you will have. The amount of foam needed depends on the type of drink you’re preparing. The stretching phase needs to happen in the first few seconds of steaming so that you will have time to break up the bubbles of infused air.
Dive the steam wand further below the surface of the milk.
A latte requires the milk volume to be expanded by approximately 20% with the added foam. A cappuccino requires the milk to be expanded longer—the added foam should almost double the volume in the pitcher. Once the desired amount foam is achieved, dive the steam wand into the milk to stop introducing air with the steam. Hold pitcher steady so that the milk swirls around inside the pitcher creating a whirlpool. Continue to texture the milk until the desired temperature is reached.
Turn off steam wand when the milk reaches the desired temperature.
Turn the steam valve clockwise to shut off the steam wand. The milk should be heated to 145ºF to 155ºF unless otherwise requested. Any hotter and the sugars in the milk will begin to break down, giving it a flat or burnt taste.
Wipe steam wand completely clean of any milk residue.
Use steam wand towel to wipe and thoroughly clean the steam wand. Any milk left on the wand will dry and harden in less than a minute. This is unsightly and unsanitary.
Purge steam wand again.
Purge the steam wand for at least 2 seconds to flush out any milk left in the wand. Milk left in the wand can work its way up into the steam valve assembly as the steam wand cools. This will clog it and cause it to steam more slowly, much like a clogged sink drains slowly. Also, it’s disgusting.
Pour milk into drink immediately.
As soon as you are finished steaming, the milk and foam will begin to separate. The foam will get dry and airy and will not have a velvety smooth mouthfeel. Swirling the pitcher will help keep the milk and foam emulsified, but this will not work for very long.
· Preheat demitasse cup by filling with hot water using the Americano wand.
· Pull shots into demitasse cup, enjoy.
· Serve in a 6 oz. cappuccino cup.
· Pour 4 oz. of milk into a small milk steaming pitcher.
· The tip of the steam wand should be just below the surface of the milk to start.
· A clip-on type thermometer works well to monitor heat. Once it’s near 140 degrees, discontinue steaming.
· While pressing down on milk pitcher, swirl the milk to blend froth into steamed milk until a wet sheen appears.
· Pour milk though center of espresso shots careful to preserve crema as long as possible.
· The heavier steamed milk will pull the blended lighter froth out of the pitcher during the later part of the pour, creating the cap.
· Macchiato simply means “marked with milk” so top espresso with desired portions of steamed milk and/or froth.
· Follow steps for making a cappuccino, however, introduce air for about 5 seconds.
· Increase the volume of the milk by at least 50% by introducing controlled amounts of air along with the steam.
· Pull espresso shots directly into cappuccino cup.
· A traditional cappuccino is equal parts espresso, steamed milk and froth.
· Preheat a demitasse cup.
· Pour 4 oz. of milk into a small milk steaming pitcher.
· Increase the volume of the milk by at least one-third by adding foam, set aside.
· Pull espresso into demitasse cup.
· Pour milk and foam over espresso and serve.
· Fill desired coffee cup with hot water using the Americano wand.
· Leave room for cream unless otherwise specified.
· If possible, pull shots directly into cup, otherwise use shot glasses. Serve.
· Preheat a cappuccino cup.
· Pour 4 oz. of milk into a small steaming pitcher.
· Pull shots into cup.
· Pour milk into shots; take care to preserve crema.
Maintenance of your home espresso machine:
· Back-flush each group with espresso machine cleaner
· Soak portafilter, baskets, dispersion screens, and dispersion screws in cleaning solution
· Soak steam wands in cleaning solution, remove and clean tip
· Clean drip tray with soap and a non-abrasive cleaning utensil
· Empty grinder hoppers, wipe with a wet towel and dry
· Wipe down espresso machine
· Empty the hopper and wipe down with a wet towel and dry
· Use the grinder brush to clear the dosing chamber of coffee grounds
· Run grinder cleaner such as Grindz through grinder.
· Be sure to grind and discard a few grams of coffee to remove any grinder cleaner residue.