How many grams of black coffee a day is more appropriate for a cup of coffee caffeine content?

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Caffeine is a thing that people love and hate. In the past, people have been refreshing and excited by eating coffee fruits and beans to get caffeine. Modern health activists will regard coffee as an "enemy". For people who love coffee and care about their health, it has always been a hot topic to discuss which coffee has lower caffeine, including the caffeine content between deep-roasted coffee and light-roasted coffee.

Which is more caffeine in deep-roasted or light-roasted coffee beans?

Some people will think that deep-roasted coffee beans will contain more caffeine, that is, as the baking degree deepens, the caffeine content will increase.

The reason for insisting on this view is that the deeper the coffee beans are roasted, the lighter the quality will be. If you need to weigh the same weight of coffee beans to brew coffee, then the quantity of deep-roasted coffee beans will be more than that of light-roasted coffee beans. Coupled with the fluffy structure of deep-roasted coffee, it is easier to extract substances, so you will think that deep-roasted coffee will contain more caffeine than light-roasted coffee.

Some people think that deep-roasted coffee beans contain less caffeine because the melting point of caffeine is 235-238 ℃. It is difficult for the average coffee roast to reach such a high temperature, but caffeine sublimates at 178 ℃, which means that the total amount of coffee in coffee beans will be reduced.

According to a report by the Association for Coffee Science and Information (Association for Science and Information on Coffee), the caffeine-to-weight ratio of an Arabica light-roasted, moderately roasted and deep-roasted coffee bean is 1.37%, 1.31% and 1.31%, respectively. That is, shallow baking is only 0.06% higher.

The weight loss rate of light roasted coffee is 11-13%, and that of deep-roasted coffee is 15-17%. Therefore, there is a slight loss of caffeine due to sublimation in the process of roasting, but these losses are negligible. For the same intake of coffee grams, the caffeine content of deep-roasted coffee is higher than that of light-roasted coffee beans because of the weight loss rate and extraction efficiency.

The degree of baking is not the key factor affecting caffeine content.

Caffeine content can be divided into two aspects, one is the caffeine content of coffee beans, the other is the caffeine content of coffee liquid.

The coffee liquid content of coffee beans has a great relationship with coffee variety and growth altitude. The caffeine content of Arabica species is about 0.9-1.4%, while the caffeine content of Robusta species is generally more than 2%, even more than 3%. The caffeine content of different subvarieties of Arabica coffee beans also varies slightly in different regions.

Reference unit of caffeine content in some important coffee producing areas:%

The higher the altitude of the same coffee variety, the higher the caffeine content, because the higher the altitude, the more light will be, and the temperature will be lower. Coffee will grow slowly and accumulate more substances while receiving sufficient nutrients. So the amount of caffeine will also increase.

People will pay more attention to the amount of caffeine in the coffee liquor. after all, not all the caffeine contained in coffee beans is extracted into the coffee liquid, and the caffeine intake we focus on is the amount of caffeine mixed into the water.

The same kind of coffee beans with different extraction methods, the content of caffeine is also different. If 15g Arabica beans are brewed by hand, the caffeine content of a serving of hand-brewed coffee is about 100-150mg (200ml coffee liquid). 1shot Arabica beans contain about 50-100mg of espresso (30ml espresso liquid).

In general, there is a key relationship between the release of caffeine and the length of extraction time. The longer the water and coffee powder, the more caffeine will be released, so the same coffee bean weighs as much as it does:

Cold extract coffee > French press > hand coffee > espresso

Is caffeine harmful to human health? How many cups of coffee can adults drink a day?

In the past, there was always a saying that children and pregnant women could not drink coffee, saying that caffeine would affect the healthy growth of children and fetuses. Although there is growing evidence that proper intake of caffeine is good for the body.

Everyone has different tolerance to caffeine, and normal adults consume no more than 300mg (about two cups of hand-brewed coffee) a day, which can relieve fatigue and have a refreshing effect. In addition, caffeine has some vasoconstrictive effects and can improve some tension headaches caused by fatigue.

But people worry that caffeine can become addictive and lead to excessive consumption that is harmful to the body. Unfortunately, the so-called "addiction" of caffeine is not as good as your "addiction" to your mobile phone. Caffeine is an irritant for the central nervous system. Frequent intake of caffeine can lead to mild dependence. If you stop taking caffeine suddenly, it will cause headaches, fatigue, anxiety and inability to concentrate. But these situations will disappear within a few days after you stop eating, and will not cause harm to the body. Only excessive intake will affect physical and mental health.

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