Why does the coffee turn sour? Why is the coffee sour? The relationship between sour coffee and cream

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The source of coffee sourness is the difference between pleasant and unpleasant acids.

My family has bought a can of ground particles of coffee used to drink very smooth very fragrant what has recently been sour, at first I thought it was creamer expired, later did not add to drink the same, in the end why??

Why is my coffee a little sour? !

Have you ever been to an orchard? Think of the fruits that grow on trees, lemons, oranges, tomatoes, plums... Which one isn't sour and sweet? If you know that coffee beans come from the bright red coffee cherries on the coffee tree, if you are willing to spend time studying the hundreds of chemical components in coffee beans and the reaction of high temperature, you can understand that coffee is originally sour! Please do not have prejudice to sour coffee, more understanding of the acidity of coffee, your coffee world will be broader.

In fact, sourness has always been a very important item when coffee experts evaluate coffee! Sour taste is mainly distributed on both sides of the tongue and behind the tongue base. In the vocabulary of the cup test report, it is customary to replace Sour with Acidity, and the word Acidity is not only the strength of acid, but also the form of acid.

The texture or type of acidity in coffee is directly affected by the variety and cultivation. Generally speaking, coffee from Central and South America such as Costa Rica, Guatemala, Colombia... The acidity is bright, clear and elegant. Asian coffee such as Sumatra and India has a rougher, darker acidity, while African coffee has a wild, crisp, grassy acidity.

When we drink coffee, we can clearly find that acidity exists in the form of fruit acids, lemon, grape, citrus, tomato, passion fruit, peach, even plum, mulberry... The fruit flavor, which can hardly be associated with coffee at ordinary times, sometimes exists alone, and sometimes appears alternately. The high-quality sour taste reacts quickly, comes quickly, goes quickly, is not dry, after stimulating the taste buds on both sides of the tongue, it turns into a continuous sweet churning up.

Seeing this, some people may begin to suspect that I am bragging. Why does the probability of drinking sour coffee seem to be not too high? The key is baking. The roaster determines the final appearance of the sour coffee. The lighter the baking, the shorter the baking time, the more acid will be retained. In other words, coffee can be made from a strong acid to a weak acid, or not at all, as long as the roaster is happy. However, such a practice is highly controversial and is outside the scope of this article.

Acidity also includes olfactory components, especially when coffee is freshly ground, because the acids in green coffee beans are converted into volatile aromatic substances during the roasting process, in addition to forming a sour taste. As the baking temperature increases, the higher the degree of caramelization, the less sour it becomes.

Some people say that coffee will turn sour when it's cold, some people say that coffee will turn sour when it's brewed at too low a temperature, some people say that it will turn sour when it's added creamer... Personally, I think it's just an excuse not to like sour taste. The taste buds on the human tongue, when the coffee has just been brewed at a high temperature, are relatively slow to feel sour, but after the coffee is cold, the reaction is sharp, resulting in the illusion that the acidity is obviously increased. On the other hand, the sour and bitter substances in coffee beans due to roasting will vary according to the water temperature during brewing, and the bitterness and sourness in the mouth are inversely proportional to each other. So, when the coffee is roasted and the ingredients inside are fixed, the polyacid is polyacid and cannot be changed. At low water temperature, bitter substances are extracted slowly, and the amount of extraction is naturally small. Although the extraction of acid is also affected, it is not as large as bitter components. In the case of reduced bitterness interference, unwitting people think that low brewing has made coffee sour.

Finally, I hope that my friends who can't agree with sour coffee will give Acidity a chance to wake up your taste buds and enrich the connotation of coffee. Maybe in the future, you will tell others like me that coffee is still sour!

Coffee beans were originally divided into four varieties, but after variety improvement and planting site influence, roughly only

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