Coffee is renowned for being a naturally bitter beverage. But in reality, if properly prepared, coffee should be balanced, neither too acidic nor too bitter.
The bitterness of a coffee is often considered by baristas to be a total and absolute flaw, whereas some people like coffee for this very reason, for the wake-up punch.
I think it’s really a question of balance. Bitterness is a natural part of coffee beans and is essential for a good cup of coffee – you just need to know how to dose it correctly.
On the other hand, there are several reasons why coffee can be too bitter:
- Balancing the recipe
- Degree of roasting
- Grain variety
Let me walk you through these options, but first, let’s agree on what bitterness is.
What is bitterness?
Sometimes confused with acidity, it’s one of the 5 primary tastes, along with salty, sweet, acid and umami. It is found in endives, tonics, certain red wines and IPAs…
This characteristic is present at different levels in all coffees, as it is created by the caffeine itself, but also by certain acids present in the beans.
In fact, an acid in the chemical sense does not necessarily result in an acid taste. Here, for example, it’s chlorogenic acid and its derivatives created during roasting that are responsible for much of the bitterness, notably quinic acid, characteristic of tonics.
On the palate, bitterness is the sensation that lingers in the back of the mouth after swallowing, very present and dry. Not to be confused with acidity, which is sharper and more active at the beginning of the mouth.
This sensation, linked to chemical compounds, can therefore be variable and more or less controlled, so let’s see how:
How can I make my coffee less bitter?
1. Recipe
A coffee recipe is made up of all the elements that can be varied to obtain a different result in the cup. The 3 main parameters are the quantity ofwater used, the quantity of coffee brewed and the grind size.
If your coffee is too bitter, this indicates that you’ve extracted too many aromatic compounds, resulting in an imbalance called over-extraction.
The extraction of coffee aromas is not linear. Oils and acidic compounds are extracted first, followed gradually by bitter compounds. The aim of a recipe is to strike a balance between these two categories.
So how do you rebalance a recipe that’s too bitter? Well, we’re going to try to reduce the time and surface area in contact between the water and the coffee, by adjusting our parameters:
- Coarsening the grind used
- Reduce water consumption
- Increase the amount of coffee
Attention The extraction time is a recipe element only in the case of infusion (Coffeemaker piston); the rest of the time, it’s a control value resulting from the other parameters.
These 3 parameters are available on most automatic machines, and if you buy your coffee directly from a roaster, you can ask him to grind your coffee more coarsely.
In addition, it is possible to modify the solvent power of water, making it less effective at extracting aromatic compounds. For example, you can lower the temperature. Going from 96°C to 80°C water can make a big difference.
You can also simply change your water for a less mineral version. It is the minerals present in water that help extraction.
If you need to reduce the amount of water, but prefer your coffee to be long and light, then lengthen it with water after extraction. In this way, you reduce the body without disturbing its balance, which is one of the most common mistakes made when preparing a long coffee.
And if you like long coffees, why not try your hand at filter coffee? Its longer infusion time allows for greater precision in the recipe and a more complex result in the cup, without releasing bitterness as easily as with an espresso.
Of course, any of the bonus ingredients in your drink can make it less bitter: sugar, honey, salt (a pinch, yes, yes!) or milk.
In the case of hot milk, take care not to heat it above 65°C. Beyond that, you start to break down the proteins, making it vegetable-based and…bitter. So it’s counterproductive.
2. Roasting
Indeed, as mentioned above, a large proportion of bitter components are developed during roasting. A more thorough roasting will result in a more naturally bitter coffee.
Secondly, a more roasted coffee is also more easily soluble, which increases your chances of over-extraction, as the water will more easily extract too many aromatic compounds, resulting in an unbalanced recipe.
You’ll need to adapt your recipe to suit your method and your coffee. Ask your roaster about the roast level of your coffee and the grind best suited to your preparation method.
Finally, a poor-quality coffee is one that, during roasting, exceeds the 2nd crack and undergoes pyrolysis. This is the appearance of black traces on the grain, similar to charcoal. The grain then takes on an oily surface. Reaching this roasting point makes coffee inevitably bitter.
3. The variety
The last important point in the presence of bitterness in coffee is its variety. If your coffee is too bitter, it may be because it contains some Robusta.
Highly prized in Italian espresso blends, Robusta is the nephew of Arabica. And no, that’s not his brother on the family coffee tree, that’s the canephora!
Growing at lower altitudes and in terroirs that are often less complex, robusta develops fewer aromatic acids, reinforcing its natural bitterness.
Robusta is popular in Italian blends because it allows you to make very short but balanced espressos, which would be virtually impossible with 100% Arabica.
On the other hand, today’s fashion is for filter coffees and long espressos, which makes the presence of robusta in a blend rather counterproductive for our much sought-after balance.
My coffee has become acidic. What should I do?
If, after several modifications, your coffee becomes acidic, salty or astringent… Back off!
You’ve fallen on the other side of the balance: under-extraction. No problem, just go the other way with your settings, and play with each one until you get the drink you want.
Perhaps, too, by fine-tuning, you can develop the natural acidity of the grain and reveal its terroir and personality. How can you tell the difference between under-extraction and terroir? Read our article on the subject!
Using a scale to weigh your water and coffee will undoubtedly help you to be more precise and consistent in your morning preparations, and consistently get the coffee you like. Because that’s what makes the best coffee!