Colombian boutique coffee Why Colombian coffee tastes more sour than other coffee?

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Colombian coffee beans, geographically speaking, belong to the Central and South American coffee belt, and the flavor of the coffee beans should be more balanced, but when I drink it, when the coffee liquid touches the tip of my tongue, I can't help saying, "Hey, Colombian coffee is so sour!"

Is Colombian coffee really sour?

From a chemical point of view, coffee is rich in a variety of organic acids, such as acetic acid, chlorogenic acid, citric acid, malic acid and so on. When we measure the pH value of a cup of coffee, we will find that the average pH value of coffee is between 5. (but in fact, the acidity of coffee does not have much to do with the pH value, it is actually more about expressing the flavor we feel when we drink a cup of coffee. )

From the "roasting point of view", this is indeed the reason why most Chinese consumers define coffee in terms of taste and consciousness: "bitter". The deeper the coffee is roasted, the more organic acids in the coffee will be decomposed (especially the decomposition of chlorogenic acid), and the more bitter the caramel reaction will be.

First of all, let's take a brief look at some of the acids in coffee (except phosphoric acid, the rest are organic acids. )

Chlorogenic acid

Robusta raw beans contain 7%, 10% of chlorogenic acid, which is higher than 5.5% of Arabica beans, which is 8.0%. During baking, chlorogenic acid slowly breaks down into quinic acid and caffeic acid, which often bring bitterness and astringency to coffee.

Citric acid

Citric acid, which comes from metabolism, reaches its maximum at medium-to-shallow baking. In terms of taste, citric acid has a strong acidity, just like tasting an immature fruit, but the tonality tends to lemon, citrus, nectarine and so on. In general, beans from Central America are high in lemons.

Phosphoric acid

This is the inorganic acid in coffee, which comes from soil and fertilizer. Although there is still 1% phosphoric acid in coffee, it is said that phosphoric acid is 100 times stronger than other acids. It is also said that phosphoric acid has no taste, but it is mixed with other acids to create BlackBerry and blackcurrant flavors.

Malic acid

It comes from cell respiration and is easy to decompose during baking. the degree of baking has been lost by 1/3, but it is the key to the existence of soluble flavor substances in the cup. Malic acid is similar to citric acid, but more balanced, adding more fruity flavor to coffee.

Acetic acid

It is acetic acid, which is mainly produced in the coffee fermentation process. With the development of baking, the content of acetic acid will increase (from the decomposition of sucrose), but will gradually decrease because of its volatility. If the acetic acid content is moderate, it will provide the coffee (sweet, clean flavor), but if too much, it will produce vinegar or over-fermentation.

Having said so much, why does Colombian coffee taste more sour than other coffees?

Coffee variety

As we all know, Arabica is grown in Colombia, and although the content of chlorogenic acid in Robusta is about 2% higher than that in Arabica, this does not mean that Robusta's coffee will be more "sour"; on the contrary, during baking, chlorogenic acid breaks down into quinic acid and caffeic acid, bringing bitterness and astringency to the coffee.

Not only that, Arabica contains more sugar and oil than Robusta. In addition to creating a stronger sweetness and complex flavor, the sugar also breaks down during the baking process, resulting in a sour mixture.

Planting altitude

Colombian coffee is grown above the altitude of 800m-2300m, and the high-altitude planting environment creates a perfect living space for coffee: low temperature makes coffee fruit ripen slowly, adequate metabolism is conducive to the accumulation of acids, temperature difference between day and night is conducive to sugar accumulation, leaf rust and coffee pests are reduced, and so on, all of which create a more complex flavor characteristics of coffee. Among them, the sour quality of fruit is more prominent. For example, in the Nalinglong producing area with an average elevation of 1800m, its citric acid is its biggest feature. In addition, coffee grown at high altitudes has higher hardness and density, so it is more resistant to baking, which makes the decomposition rate of acids slower.

Treatment method

The vast majority of coffee in Colombia is washed, and the process of desquamating and degumming filters out some sucrose and fructose, increasing acidity; the fermentation process of washing is also conducive to the production of acetic acid. On the contrary, the sun is first treated with complete fresh fruit, and the sugar-rich pulp layer does not leave the coffee raw beans, thus increasing the overall sweetness.

Acidity is an essential part of a cup of coffee, they are active, bright, smooth, or fruit-like, but they can also be sharp, sour and so on, giving our taste buds a rich space to explore.

In addition, different acids show different flavor characteristics under different roasting degrees, so the "more sour" Colombian coffee has "higher plasticity" when roasting. The flavor characteristics will also be "more layered". Of course, this is also a test of the craftsmanship of all bean roasting artists.

Of course, the acidity of the coffee presented in front of us is not only affected by several factors, but also related to the baking method, brewing method and temperature, and the thickness of grinding particles. Even the three points I have listed cannot fully summarize "Why Colombian coffee tastes sour than other coffees" from the perspective of origin, including soil, precipitation, microclimate, planting methods, and even the age of a coffee tree is related to the presentation of coffee flavor.

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