Shallow roasted coffee beans Why is my coffee so sour?

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In fact, coffee itself is an acidic drink, whether coffee is sour or not depends on the baking degree of beans. The longer the roasting time is, the higher the caramelization degree is, the more acidic substances are destroyed, the less sour the coffee is, the shorter the baking time is, the lower the caramelization degree is, and the less acidic substances are destroyed. It is easy to make sour coffee, that is to say, the roasting degree is inversely proportional to the sour taste. The deeper the roasted coffee is, the more sour the coffee is, and the shallower the roasted beans are. In addition, 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 drink the coffee while it is hot, otherwise the sour taste of the coffee will appear as the temperature drops. The preference of coffee roasting degree from country to country often varies from region to region. In principle, the baking degree in Italy is getting deeper and deeper from north to south. Milan in the north of Italy is roasted deeply, and the coffee is slightly sour, while Rome in the south is heavy-roasted and the coffee has no sour taste. The roasting of coffee in the United States is getting lighter and shallower from west to east, that is to say, the roasting degree of West Bank cities such as San Francisco and Seattle is deeper than that of New York or Washington. West Bank coffee is darker and more bittersweet than the East Coast, while the East Coast prefers a more lively sour taste, mostly deep roasting or shallow roasting. The baking degree in Taiwan is deeper in the south than in the north. There is no market for sour coffee in southern Taiwan, but there are a small number of eosinophiles in northern Taiwan, and shallow roasting is still a small market. Caffeic acid is not a 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.