Getting a perfect shot of Espresso is not an easy thing. You either end up with a shot that is too foamy, or there will be no layer of Crema over your Espresso shot.
There are many small factors that affect the taste and texture of your Espresso shot. Like the quality of coffee beans, the size of coffee grounds, the amount of coffee grounds for the shot, and the tamping coffee grounds in the portafilter. You can only achieve a level of perfection with experience.
The layer of foam on the top of Espresso is inevitable because of pressurized extraction, and the perfect layer of Crema is the sign of a freshly brewed shot of Espresso. It makes your Espresso more beautiful and aromatic.
The taste of Crema is way more bitter than the Espresso itself. So, the very thick layer of Crema is certainly undesirable as it makes your shot very bitter.
So, why is my Espresso foamy or bubbly?
There are three reasons why your espresso is too foamy. Dark roasted coffee beans create more foam than light or medium roasted beans. Or, if the grounds are too fine, the shot will be over-extracted and have a thick layer of foam. In addition, too much pressurized water also creates a thick layer of foam.
4 DIFFERENT REASONS of Espresso Crema too foamy or bubbly
If the layer of foam or Crema is too thick on the shot of Espresso, it will make the taste of your coffee burnt and very undesirable.
Four different factors affect the thickness of foam over your shot; the quality and Freshness of roast, the ratio of water to coffee grounds, the size of coffee grounds, and the temperature and pressure of water. Let’s discuss each factor in detail.
i) Quality and Freshness of roast
The thickness and color of Crema tell us a lot about the Freshness and quality of coffee beans.
Carbon dioxide gets trapped in the coffee beans during the roasting process. So freshly roasted coffee beans will have a large amount of carbon dioxide, and it gets dispersed in the environment with time.
If you buy freshly roasted coffee beans from a local roaster, then the layer of foam will be very thick on your shot. So, it’s recommended to let them sit for at least 4 to 5 days before using them.
Conversely, if the coffee beans you are using are very old, there will be no crema over your shot, which is also not a good sign.
Dark roasted coffee beans have more carbon dioxide because of the prolonged roasting process. That’s why they create form.
So, if you use dark roasted coffee beans and facing the problem of a too thick layer of foam, then changing the type of roast might solve your problem.
The thickness of foam also depends on the type of coffee beans. Robusta coffee beans create more foam than Arabica beans. So, if you are facing the problem of too thick foam, using 100% Arabica beans might solve your problem.
Lavazza coffee beans are my personal favorite. You can buy them from here
Check out our article on the best coffee beans for Espresso. I have compared the flavors and qualities of 10 different espresso beans.
iI) Size of coffee grounds
The perfect grind size for Espresso is fine. If you use coarse coffee grounds to make Espresso, your shot will remain under-extracted, it will be very weak and there will be no layer of Crema over it.
And if you are using coffee grounds that are too fine, the Espresso will become over-extracted, and you will get a very thick layer of foam.
So, it’s your task to find the grind size that will result in a perfect layer of Crema. Experiment with 6 to 7 different grind sizes in the fine range, and you will surely get the best result.
iII) The ratio of coffee to water
The ratio of coffee to water alters the taste of Espresso as well as the layer of foam over it. The Crema will be thick if you use too many coffee grounds for brewing a shot. And If you are using too few coffee grounds, there will be very little or no layer of foam over your shot.
The ideal ratio of coffee grounds to water is 1 to 2. That means for 40 grams of water; you should use 20 grams of grounds. But you can adjust this ratio according to taste.
You can get a better estimate by measuring the brewing time. The ideal shot of Espresso should take 25-30 seconds.
If your brew is taking longer than that, the layer of foam will be very thick; try reducing the grounds in that case.
And if your brew takes less time than that, there will be no Crema, or it will be very thin, try increasing the coffee grounds in that case.
IV) Temperature and Pressure
The higher the temperature and pressure, the more carbon dioxide will get trapped, resulting in a very thick layer of foam.
I am discussing this factor at last, as most espresso machines automatically adjust the temperature and pressure of water, and you have no control over it.
The ideal pressure for brewing Espresso is around 9 bars, and the ideal temperature is about 195 to 205 degrees.
So, if your Espresso machine gives you control over the temperature and pressure, try adjusting it around these numbers; you will get the best results.
Is Espresso supposed to have foam on top?
There is a thick reddish-brown colored layer of foam on a freshly brewed shot of Espresso, often known as Crema. This layer of Crema looks very delicious on the top and has a very flavorful aroma.
But what actually Crema is, and how is it formed?
During the roasting process of coffee beans, carbon dioxide gets trapped in oils present in the coffee beans. When preparing a shot, pressurized hot water is forced to pass through the coffee grounds, which extracts flavors from the coffee grounds and also the carbon dioxide gas. And when we bring the coffee water (Espresso) to normal pressure after brewing, it can no longer hold the carbon dioxide. Some of it gets dispersed to the environment, and some of it sticks to molecules of coffee and water, creating a foamy and bubbly layer on top. This layer is called Crema
Crema is the essence of Espresso; it is formed due to the pressurized brewing process, which is unique to Espresso. This layer of foam doesn’t form in other brewing methods, as all other methods like pour-over, Chemex, drip coffee, etc., don’t use pressurized water.
What does Crema taste like? Should you stir it or skim it?
The taste of Crema is not as beautiful and delicious as it looks. It tastes more bitter and burnt than the actual Espresso under it.
So, should you stir the Crema in the shot or skim it out of the cup?
This question has been in debate for many years. Some experts suggest stirring it while some suggest the opposite to it.
Well, it mainly depends on your taste. If you hate bitterness, then you should skim the layer of Crema. It will remove most bitterness from your shot, and sweet flavors will become dominant.
If you are like me and like the bitterness in the taste, you should stir the shot before drinking it.
The cream layer should either be skimmed or stirred and not left as it is.
If you don’t do it, the flavor you get will not be balanced. It will be very bitter at the top and sweet at the bottom. I like bitterness in Espresso but not alone; it should be mixed with other flavors of Espresso to get a perfect balance.
We have prepared a list of 10 best portable Espresso makers. With these machines you can easily make espresso everywhere.
A layer of Crema or foam is the indicator of the Freshness of your cup of coffee and makes it flavorful and aromatic. But it becomes a problem if it’s too thick as its taste is not much pleasant.
Baristas recommend that the layer of Crema should not be thicker than 1/10th of your cup. If it is thicker, it will make your shot bitter and bubbly.
I am Johny Morrisson! Founder of CoffeeAbout
My love for coffee dates back to my childhood. I love trying out different coffee machines and recipes.
As a coffee enthusiast, I decided to start my blog last year to provide users with useful information on brewing methods.
During this journey, I have discovered many new things and facts about coffee that I will share with you here.