Crema on Espresso - What is crema, and why is it important?

As a Barista that also works in retail, I often hear comments from my customers such as “I want a coffee with Robusta because that makes better crema”, or my favourite one, “A good espresso has a thick crema”.

For a lot of people, the importance of crema is clearly bigger than what I actually believe it to be, at least as an indicator of coffee quality. For this reason, in this blog post I want to talk about why coffee has crema, how it tastes, what it tells us about extraction, how important it is for the taste experience. Importantly, I want to talk about how marketing has implanted a picture of crema into the consumers head that is seriously questionable.

Why does coffee have crema?

During the roasting process, coffee builds up a high concentration of CO2 (carbon dioxide). Whenever you brew a freshly roasted coffee, you will notice that it starts bubbling and expanding as soon as the hot water hits the dry coffee bed, or when it pours out of the portafilter. In filter coffee, we refer to this as “blooming”, an important step to release the CO2 out of the coffee and to prepare the coffee to give us all of it’s beautiful flavour.

When we are making espressos, the pressure that we use is much, much higher than just gravity methods like filter coffees, such as pour overs. The water that passes through the coffee bed with up to 9 bars pressure can hold much more of the existing CO2 from the coffee; as soon as it passes through the coffee, the pressure dissipates from the liquid. The CO2 that was extracted due to the pressure from the machine now pops into million little bubbles that rise to the surface of the espresso. These millions of little bubbles form a layer, which is what we call ‘crema’.

You might notice more crema on fresher coffee as it still contains more CO2; similarly, you will notice less crema on lighter roasted, or older coffees. This is valuable information for every barista as we can now react on the way that we dial in our coffees, using different brewing temperatures and grind sizes and maybe even adjusting the pressure of the machine. What it doesn’t tell us is, if a coffee is good or bad – it’s just different.

A (super) short history of espresso

Let us go back in time to the start of the 20th century. Back then, the vast majority of the coffee sold in Europe was Arabica. Italy has just invented the commercial espresso machine, a big hot boiler that made espresso with pressure. Unlike our machines today, you couldn’t set back then was the temperature - so all the coffee was made with water that was nearly 98-99 degrees C.

By our current standards, this temperature burned the coffee and made it bitter but nevertheless, this was the first espresso introduced to the European market. Then, there was a period of very difficult times between the economic crisis, war and more war. Coffee was not the most important thing that people had to worry about, so the USA was able to benefit from their close access to coffee in the America, and bought more coffee to be used in their traditional filter coffees.

After World War II, the European economy slowly got better and people wanted to finally drink (more) coffee again. So many people, in fact, that the market couldn’t keep up with the demand. So, producers and importers researched and discovered a species in 1897 that was easier to grow, cultivate and be grown at a wide range of altitudes: Robusta. As it was easier to cultivate, the caffeine content was higher and the beans were generally quite large, it was easier to make more profit. The only problem was that it tasted completely different to the more commonly known species, Arabica. In comparison, Robusta was bitter and harsh - however, it produced much more crema.

The idea was to use smaller amounts of the bitter Robusta coffees, and to blend them with the higher quality Arabica beans, in order to cover the growing demand. From this, the classic 80:20 coffee blend was born. To make the difference between both coffees less obvious, the industry roasted all the coffees quite dark so that the consumer couldn’t taste the difference anymore (or they just didn’t know how to roast well). Importantly, some really smart marketing people remembered that the machines at the start of the century were so hot, that they mainly produced bitter coffee. That was a perfect disguise for the new also very bitter coffee and the phrase “Italian roast” was established.

This style of coffee was so bitter that it was nearly undrinkable without sugar. So, these clever marketing people advertised these blends with phrases like ‘Your crema should be so thick, it has to hold the sugar for at least x amount of time.’ Some companies referred to this as the “sugar test”, and in some places is still considered a mark of quality for espresso. Even today, in some parts of Italy many people say "Quando il cucchiaio sta a piedi, c'e abbastanza zucchero nel caffe", which roughly means, "When the spoon stands up straight, there's enough sugar in your coffee".

I still remember these advertisements, and have experienced the 'sugar test' and 'spoon test' first hand on my trips to Italy. These ads, combined with the persistence of these 'tests' during the emergence of modern coffee culture, have resulted in many people thinking that this is how espresso was supposed to be consumed. But the question remains – why add sugar if you could just start drinking coffee that is not unbearably bitter?

So, a quick recap:

The consumer wanted coffee, the market found a cheaper coffee, and blended and roasted it very dark. This resulted in bitter coffee with lots of crema. This is how generations of people drank coffee and think that this is the only way how coffee should taste like. And that is ok. I’m not in a position to tell people that their perception of taste is bad, because taste is heavily involved with emotions – if that was the first taste experience they had and this moment was really nice, they will always say this is the best taste. What I can do is tell people there are other tastes which are more delicate, more refined and less bitter, and I can invite them to discover it with me. This way, we can celebrate new coffees that focus more on the product, rather than on the marketing.

How does crema taste?

If you ever drink just the crema of a coffee you will realise that it tastes quite bitter and harsh, kind of like if you only taste the foam of a draft beer without drinking the refreshing liquid itself. And it makes sense. It is, after all, a lot of CO2 and it binds a lot of the non soluble substances in the coffee like small particles, oils and sometimes even ash.

Now that sounds horrible and it nearly gives me the feeling I should take the crema completely off the espresso. But sometimes a little bit of bitterness can add a new dimension to your espresso, especially if it is a lighter roasted coffee. Every time I drink an espresso I take a spoon and stir a couple of times. This way I can mix all my layers and experience the full potential of the coffee. It also helps to cool down the espresso, and that also often reveals more sweetness and clearer fruit structures.

What can we see in the crema?

You might notice sometimes that the crema in an espresso has dots or even ‘tiger stripe’ patterns (see image below). These are the visual representation of your extraction. If the contrast is super high (meaning you have really dark spots in your crema), that can show an over-extraction of your coffee, meaning it has extracted too much and can taste bitter. A pale light beige crema can show you under extraction, which results in a sour coffee with little body.

Your crema might also change depending on the shape of your cup. Smaller cups will hold more crema, as the millions of little bubbles are in a thicker layer and will take longer to dissipate, whilst wider cups will spread the crema into a very thin layer and disappear more quickly. Taste testing different espressos, I have come across light roasts that are incredibly elegant and clean and when served in a wider cup, this coffee will have a heavier body and a different mouthfeel than it would in a classic espresso cup.

A very thick crema can be a sign of a very fresh (maybe too fresh) coffee; or on the other hand, it can mean that the roast was super dark. So actually, the commercial image of a super thick crema with lots of tiger stripes on it would be a coffee that I and many other specialty baristas probably wouldn’t enjoy drinking.

How important is crema for our taste experience?

Despite what I have said above, crema is an important part of espresso. An ideal espresso is one that is balanced – not leaning too much into sweetness, fruit qualities or florality, but one that encompasses sweetness, acid, bitterness and different expressions of tactile (mouthfeel and texture). In this way, the bitterness, thickness and occasional oiliness of crema is an important part of balancing out the thinner, more sharp and more acidic components of the espresso that are in the lower layers of the cup.

If you mix the crema with the rest of the extracted liquid, it can give you this creamy or silky mouthfeel, as well as add body and texture to your espresso. What I find so exciting about this is that the amount of stirring and mixing you do will change the temperature of the espresso, which will change the taste experience (ever heard a barista competitor say "Stir 5 times"? That's why).

When I dial in a new coffee, I taste it with different recipes of course, but once I am satisfied with my extraction, I start stirring it for different times and then tasting it. For example, stirring twice you might get dark chocolate; stir 5 times, you get a nougat quality. This is incredibly exciting and these are the experiences that you can easily communicate to your customers - trust me, I have done it so many times and yes, maybe I get carried away and am way too excited about flavour in general.

Customers are generally interested in the change of flavour and also about me telling them about how to experience this change. This can aid baristas when talking about crema, saying things like "The crema itself isn't the best part, it's when you mix it all in that the espresso becomes balanced", or "Try tasting the coffee straight away, and then stir it 10 times and taste again - it will be much better and taste like x, y, and z."

I hope you found this little excursion into crema helpful – if you have any feedback or questions, don’t hesitate to message me and if you like, please feel free to like and share it!

Thank you for reading!

Nicole