You took the time to backflush your high end coffee machine yesterday, and this morning you spent few precious moments adjusting your grinder, cleaning the chute from old residue and being extra careful with your routine. You wanted the same body and complexity you are used to with your espresso, when your machine is clean and you're right into it.
You made an espresso and it tastes flat, dull, thin and quite watery, so you think: 'what did I do wrong NOW'?
Sounds familiar? Frustrating? It sure is.
You forgot that you've overstocked on beans last order and that your current bag is already a month old.
You got everything right EXCEPT the beans, one out of the 4 pillars of good espresso.
Don't get me wrong, it happens to us too, and we are occasionally reminded through a nasty, unpleasant cup, so it's good to re-visit the fundamentals of espresso once in a while, even if you are a seasoned Home Barista, so that troubleshooting is easy and you can bounce back with a quick fix onto the right flavour path.
Ideally, espresso should pour nice and slow, present a thick, golden honey crema, have a potent aroma, taste balanced (not too bitter, sweet, salty or sour). It should be velvety and smooth. A perfect espresso is enjoyable straight with no additives, yet bold enough to not disappear in milk. A pleasant and aromatic aftertaste would linger on the palate for several minutes after consumption.
So how do we get all that in cup? Results will depend on:
The 4 M’S of Espresso make sure all those ingredients are covered:
The ‘Macina’ (The Machine)
The right machine is the one that delivers the right temperature and pressure for the espresso. We look at:
- Water temperature - should be stable and somewhere between 86°C-96°C, resulting in consistent espresso
- Water pressure - the water forced through the espresso should be between 9 to 10 bar of pressure. This pressure is responsible for the development of the crema (which are the aromatic oils extracted from the powder)
- Boiler pressure - The boiler pressure determines the amount of water to be incorporated in the steam. If your milk is not foaming correctly, you may want to experiment with different boiler pressures, but this should only be altered by professionals. You can check your boiler pressure by looking at the boiler pressure gauge on the front of most espresso machines
More on how to choose the right coffee machine for you here...
The Macina-Dosatore (The Grinder)
A high quality burr grinder is essential for espresso. Burrs, as opposed to domestic grinders with blades, will crush the grind more evenly. In our experience, newbies commonly underestimate the importance of the grinder. Generally speaking, to achieve the best result in the cup, machine and grinder should be evenly matched. More on how to choose the right grinder here...
The Miscela (The Beans)
There are five main factors that impact the espresso flavour:
- Origin: Single Origin or a Blend? Blends incorporate few single origins, to create more body and more complexity, mainly to cut better through milk
- Processing method, wet or dry?
- Freshness: use at home whole beans, up to 3 weeks from roasting date. Remember: ground coffee will go stale after 3 minutes, so grind as you go!
- Roasting: roast level will impact the taste in the cup. We may be able to get balanced flavour with our espresso, city roast, however if beans are roasted lighter for filter, your cup can taste very bright
- Storage: light, heat and humidity are coffee’s worse enemies
Click here for more on how to choose the right coffee beans
The Mano (The Operator)
- Dosing - Coffee must be freshly ground to achieve peak flavors. Grind and dose on demand. When someone orders an espresso, grind only what is necessary for one shot, dose properly, tamp, and brew. Discard any espresso grounds that are not used within 30 seconds
- Distribution - Distribute the coffee evenly after dosing in the porta-filter before tamping
- Tamping - Tamp the coffee once very evenly with consistent pressure each time. The right pressure is the one that enables you to be consistent with you routine
- Extraction time - Extraction time to fill two 30ml cups between 25-30 seconds (if using the double portafilter). The goal is to have a golden honey crema for approximately 25-30 seconds with no change in color
- Environmental Factors - Humidity and temperature will change throughout the day. Since coffee is hygroscopic (absorbs moisture), the grind size must be changed throughout the day to achieve a brew time of 25-30 seconds. Temperature will not affect the espresso as humidity will, but it is important to avoid exposing the coffee to any high temperatures until brewing
- Espresso cup - The espresso cup should be pre-heated. Preferably, it will have thick walls to retain heat
- Practice - I cannot over-stress the importance of practicing and experimenting. The key to espresso is to realize that it always has further potential. By changing any one of these factors you can improve or diminish its potential
Espresso making is an art that demands the precision and dedication of science. I have never achieved, nor have ever seen a perfect espresso, although few got quite close. A perfect espresso is more of a concept than an actuality. There is beauty in the notion of espresso being volatile and difficult. If it were easy we would develop a machine that can brew a perfect espresso every time. There are so many factors involved in espresso preparation that only a human mind and a passionate heart can begin to understand and control its complexity.
Di Bartoli is really good in demystifying the belief in coffee professionals to be the only ones to understand and control this complexity. As home baristas, once we cover the basics above, we can start exploring with different gadgets like dosing or distribution tools to improve our dose / leveling consistency, we can experiment with naked portafilter extraction to bring more flavours or make the shot 'cleaner', we can book ourselves for training for guidance with our routine, we can also start exploring with lighter roast beans and possibly consider upgrade our gear to provide that extra stability and clarity into temperature and pressure environment.
And once in a while, when things go pear shape, go back to the basics!