The sour taste comes from the processing process
Each type of coffee has acidity (pH), and this acidity varies depending on the type. In our country, Arabica coffee beans are often fully washed to ensure maximum flavor and premium quality of this coffee variety. And the characteristic of the wet processing method is that it will taste more sour than the dry processing method.
The reason is that in the wet processing process, the coffee cherries are milled, put through a water bath to filter the slimy outer layer, then the coffee is fermented for about 12 - 36 hours. It is the amount of acid remaining on the coffee beans after washing that gives the sour taste. However, this is the most ideal processing method for Arabica beans so it has an interesting sour taste, not too sour.
For Robusta beans, using the wet processing method will also create a very sour taste, because Robusta beans have a higher acid content than Arabica beans. Therefore, to reduce the acidity of Robusta coffee, people will prioritize the dry processing method. At this time, the taste of Robusta beans is also sour but much milder.
Sour taste from roasting process
In addition to preliminary processing that will change the acidity of coffee, the roasting process will also have an impact. Because roasting will change the acid composition in coffee beans.
When drinking light roasted 100% Arabica coffee (light roast or medium roast), you will feel a lot of sourness. However, if this Arabica bean is roasted darkly (medium dark ro or dark roast), you will feel the acidity gradually decrease.
The same goes for Robusta beans, the color of light roasted coffee will give a more sour taste than if roasted darkly. Many Vietnamese people often do not like the sour taste of coffee, so if based on the customer's preference, Robusta beans roasted to a medium or darker level will create a more bitter taste and no sour taste.
So, in reality, pure coffee and delicious roasted coffee often have a bit of a sour taste. Besides the delicate sour taste, there is a mild bitter taste and a passionate and seductive aroma, different from the harsh bitterness and pungent smell of coffees mixed with soybeans or burnt popcorn.
With Aeroco Coffee's sharing, you must be less confused because coffee has a sour taste. That is the natural sour taste of coffee, in addition, the sour taste from harvesting a lot of green cherries, sourness due to the preparation process or leaving coffee for a long time reduces the quality of coffee is a different story. So enjoying coffee is an art. From the moment you feel the gentle bitterness, the sour taste, the unique aroma, to the sweet aftertaste in your throat and the emotions left behind. And that is when you fully feel the coffee flavor with all the sophistication of your senses.