The bitterness of coffee comes from the roasting of coffee beans during the processing.
In western countries, people drink a cup of coffee every morning. In order to cover up the bitterness of the coffee, they often add some milk powder and sugar. But why is coffee bitter? A seemingly simple problem has been bothering scientists for decades. Now, scientists have narrowed down their research and targeted two chemical molecules. At the annual meeting of the American Chemical Society, scientists reported that the two bitter chemical molecules were produced during the processing of coffee, a discovery that could revolutionize the coffee processing industry.
When you drink a cup of coffee, you actually drink a mixture of more than 30 chemicals, some of which give off fragrance, some make the taste better, and some have something to do with sour taste. Since the 1930s, scientists have begun to separate chemicals from coffee, and many flavor-related chemicals have been separated from coffee by scientists, but no bitter chemical molecules have been found.
To make the discovery, Thomas Hoffman of the University of Technology in Munich, Germany, and his colleagues once again separated the brewed coffee. They found that the chemical molecule with the smallest molecular weight in coffee tastes the bitterest, and this molecule becomes the object of further study. After analysis by mass spectrometer, Hoffman identified one of the molecules, chlorogenic acid lactone, which is a decomposition product of chlorogenic acid (found in almost all plants). Hoffman's team then prepared a series of different coffees to determine the content of chlorogenic acid lactone.
They found that when roasting coffee beans, it triggers a chain reaction in which chlorogenic acid is first broken down into chlorogenic acid lactone, and if baking continues, chlorogenic acid lactone breaks down into another substance, phenyllindane. Although lactone will only produce mild bitterness in mild and moderate roasted coffee, the secondary decomposition products of lactone will produce strong bitterness if the coffee beans are roasted for a long time.
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The strange habit of drinking coffee in Italy costs extra if you sit down and drink it.
Italians love coffee, so cafes are springing up everywhere. But you may not know that authentic Italian coffee is drunk standing up. It turns out that Italy is narrow and densely populated, with an inch of land and gold. If so many cafes were seated, it would not only occupy an area of land but also cost money. So they chose to drink it standing up. Anyway, the authentic Italian steamed coffee is very strong and refreshing, even if it stands for a while.
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Drinking coffee regularly may increase the risk of high blood pressure
According to Xinhua News Agency, according to Finnish media reported on the 28th, a new study by Finnish researchers shows that people who drink coffee regularly have a higher risk of high blood pressure than those who do not drink coffee. Researchers at the Finnish National Institute of Public Health followed about 25000 Finns between the ages of 25 and 64 for 13 years. The results show that people drink coffee more often than people who don't drink coffee.
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