Why is some coffee sour?

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Influencing factors of Coffee acidity

Affected by the coffee raw bean itself.

The acidity of coffee is affected by the quality of raw coffee beans. In terms of variety, the original Arabica is sour than the original Robusta, while in terms of elevation, coffee grown in the highlands is sour than that in the lowlands, and then the beans that have just been harvested are sour than those that have been put for a while after harvest. Good quality, high moisture content, and powerful freshly harvested beans, if they can be heated properly to produce a moderate sour taste, will make the coffee taste better and make people feel more deep.

Affected by the roasting degree of coffee

The acidity of coffee is also related to harvest, storage time, baking and brewing, and bitterness constitute the two major elements that affect the quality and taste of coffee. The sour ingredients in raw coffee beans are citric acid, malic acid and quinic acid. Phosphoric acid, etc., but this is not the sour taste we feel when we drink coffee. The sour taste we taste mainly comes from the acid produced in the baking process.

Most bakers will think that deep baking will increase the bitterness and destroy the sour taste, and shallow baking can experience the sour taste more clearly. In fact, such an idea is really wrong. Shallow roasting can easily lead to uneven internal baking of coffee beans, that is to say, in the shallow roasting stage, the internal dehydration of coffee beans is not clean enough, and the beans are extremely hard. The acidity of such coffee is often not round enough, with a kind of irritation in the acid, not high sweetness, not strong mellow, and the aroma is often mixed with a kind of grass flavor.

The sour taste of shallow roasted coffee can also be defined by technology, that is, the so-called PH value (pH value). The PH of coffee drinks depends on the degree of roasting. For breakfast coffee with shallow roasting degree, the pH value of Full City is between 4.5 and 4.7, the pH value of medium and deep roasted coffee is about 5 to 5.5, and the PH of deep roasting (Dark Roast) is above 5.5. As far as ordinary people's taste buds are concerned, when the pH value of the beverage exceeds 5.5, it is difficult to detect the sour taste. For drinks with a pH value below 5, it is easy to drink sour taste, so shallow baked beans will have a sour taste.

To sum up, all the shallow roasting of coffee is sour, which is the wrong taste released under the wrong roasting degree. The roasting degree is inversely proportional to the sour taste. The deeper the coffee is, the less sour the coffee is, and the more sour the beans are.

Affected by the water temperature of brewing coffee

The temperature of brewing coffee also has an effect. Water with a lower temperature is certainly more likely to make sour coffee than a slightly higher water temperature. I am afraid that the sour people had better finish the coffee while it is hot, otherwise the sour taste of the coffee will appear as the temperature drops.

Choose coffee beans according to taste

In fact, whether the coffee acid is sour or not is not the criterion for judging whether the quality is good or bad or whether it is fresh or not. it is all a matter of subjective taste. If you are afraid of acid, you will choose deep baked beans or Asian beans, and if you are acidophilic, you will drink shallow baked beans or African beans.

If you like sour coffee with a changing sense of taste, you might as well buy light-roasted African and Central American beans:

Such as Kenya, Ethiopia, Yemen Mocha, Guatemala, Costa Rica and so on, are good sour beans.

Consumers who prefer strong, sweet coffee can choose Asian deep-baked beans or aged beans:

For example, Indonesia Mantenin, Java, Indian beans and Brazil in South America are all good choices.

It should be emphasized here that although the sour taste of Asian beans is low, they will still taste sour if they are roasted shallowly, but the Asian beans are not lively enough and feel a little sour, which is far less varied than shallow baked beans in Africa or Central America.

What do you do with sour coffee?

After choosing the appropriate producing area and baking degree, you can basically avoid coffee that is too sour to accept, but there will be one and a half times, when you encounter a shop that loves fruit acid as much as a senior, what if you still feel sour enough to frown? Here are a few ways to manually adjust the acid to revive the coffee in front of you:

1. Slow drink: the sour taste varies with the weight of the entrance, so the impression of sour taste in small sips will be less obvious.

It is often the first impression that scares people to death, and if it is not so difficult to accept after a small number of mouthfuls, the taste buds can usually gradually feel sweetness and other flavors, which is an interesting phenomenon that changes the flavor of drinking.

two。 Maintain temperature: first of all, the sour taste of coffee with high temperature is weak, and if it is a single product with poor grade, there will sometimes be irritating and sharp sour taste after cooling, which is the main reason why coffee must be hot to drink.

Therefore, it is a good way for beginners who are afraid of acid to keep the temperature of the coffee, but not to return it to the bar to reheat it, but to add a small amount of hot water to increase the temperature, which is also in line with the third adjustment method: add water and rinse.

3. Add water to flush: in brewing and adjusting acidity, it has been known that if the amount of water increases, the sour taste is less obvious and will highlight the sweetness, which is also effective for sour coffee already out of the cup.

Therefore, you can ask the store for a cup of boiling water and add a small amount to the over-sour coffee (about 20c.c each time), which can lift the temperature of the coffee, reduce the acidity, emphasize sweetness, and reduce the sour taste that is too exciting.

But pay special attention not to add too much hot water at once, after all, the concentration will affect the taste of the coffee, 20c.c will change the composition of the entire cup of coffee, if it is still too sour, it is not too late to add it a second time.

This step of adding hot water can be repeated 2-3 times, and it is also a good way to experience the flavor changes of fine black coffee at different temperatures.

4. Pay special attention-it is strictly forbidden to add sugar, cream, milk, whipped cream, any seasoning you can find: if the coffee tastes bad, the seniors do not object to adding some sugar milk to cover it up. After all, some people think that if you pour out more than a hundred cups of coffee, you will be killed by Lei Gong (seniors don't drink because they don't do less bad things), but this is bad coffee, not sour coffee.

Coffee is so sour that it is not too bad to drink, but the addition of seasonings such as sugar milk will destroy the sour taste directly, and you will not be able to drink elegant refined fruit acid. And usually milk products encounter sour black coffee, the taste will become very disgusting, and even cause the association of sour milk, so be sure not to add sugar milk.

Small summary

1. Arabica has high acidity, Robusta has low acidity.

two。 The acidity of washed beans is high while that of sun-dried beans is low.

3. The acidity of light baking is high and that of deep baking is low.

4. The sour taste of fast baking is relatively bright, but improper handling will lead to acidity; slow baking sour taste is relatively soft, but improper handling will lead to dull.

5. When made at high water temperature, the sour taste is relatively bright, but high water temperature will reduce the acidity; when made at low water temperature, the sour taste is relatively dull, but low water temperature will increase acidity.

6. High altitude beans have higher acidity than low altitude beans.

7. Rough grinding will increase acidity, otherwise it will decrease acidity.

8. A short soaking time will increase the acidity, otherwise it will decrease the acidity.

9. Coffee without acidity is bad or even bad coffee.