Questions and answers on the introduction to Coffee

What do you know about coffee? There are 21 questions to help you understand coffee and the story behind coffee.

one。 Know caffeine

Answer: the caffeine in coffee is insoluble in cold water, but easily soluble in hot water. Caffeine can stimulate the cerebral cortex, eliminate drowsiness, increase feeling and thinking, and can be used as a cardiotonic agent to adjust the function of the heart. it also has the effects of dilating kidney vessels and diuresis. However, caffeine is not limited to coffee. Usually a cup of 100cc coffee contains caffeine 60~65mg, green tea has 200~300mg, black tea has 350~400mg, and cocoa has about 100mg. Excessive caffeine intake is prone to tinnitus, myocardial hyperactivity (the heart beats rapidly, the number of pulses increases), and the pulse is uneven, so you must drink coffee in moderation.

two。 Why is it easier to stay awake when drinking coffee?

A: many people have the experience of being too excited to sleep after drinking coffee, because there is a conductive substance called adenosine in the human body, which can control nerve activity. produce slow breathing, reduced mood, reduced gastric acid secretion and diuretic effects. On the other hand, caffeine will fake adenosine, making the body think that the effect of adenosine has taken place, making you feel energetic, increased stomach acid, urinate more frequently, and naturally less willing to fall asleep. It is worth noting that the brief awakening caused by this caffeine does not mean that physical strength is really restored. In addition, everyone has a different metabolic rate of caffeine, so their sensitivity to caffeine varies, so some people don't feel that their sleep is affected after drinking coffee.

three。 Will coffee cause calcium loss?

A: in recent years, as Chinese people pay more and more attention to the problems of calcium loss and osteoporosis, they also have considerable doubts about coffee. As for the relationship between caffeine intake and osteoporosis, there is no direct evidence that caffeine causes osteoporosis, but some studies have shown that caffeine increases calcium excretion. Therefore, it is suggested that coffee lovers should eat more high-calcium foods to supplement calcium, such as preparing cheese slices or cheesecake with coffee, which can not only supplement calcium, but also make the coffee more delicious.

four。 What is the best drinking temperature for coffee?

A: the best drinking temperature for coffee is 85-88 degrees Celsius. The taste of a good cup of coffee should be consistent when the temperature is high or low, which is why the test appraiser of coffee will evaluate the whole process of coffee from hot to cold. After cooling, a good cup of coffee will taste even better than when it is hot, except for less aroma. But because of the unstable nature of coffee, it is mostly encouraged to drink while it is hot. On the other hand, when a cup of hot coffee is in front of you, drinking while it is hot is coffee etiquette.

five。 Coffee is a beauty killer?

A: so far, none of the studies have shown that caffeine and melanin in coffee are absolutely related to increased melanin or aging of the skin. On the contrary, a moderate amount of caffeine can speed up metabolism, promote digestion, improve constipation, and improve skin roughness. About caffeine can accelerate metabolism, there is a saying that coffee will accelerate the burning of calories, to achieve the effect of weight loss, basically the theory is correct, but this kind of calorie burning is not enough to lose weight. If sugar and cream are added to the coffee, the calorie calculation is even more inconsistent with the principle of weight loss.

six。 Which people are not fit to drink coffee?

Answer: patients with cerebral hemangioma are not suitable for drinking coffee. Patients with heart disease should drink coffee without or without caffeine, because caffeine increases the heart rate and causes anoxia in the heart. In addition, patients with skin diseases and those with stomach problems should drink as little coffee as possible so as not to worsen their condition due to excessive consumption. People with diabetes should also avoid drinking coffee with too much sugar so as not to aggravate the condition. The US Food and Drug Administration (FDA) has issued a statement advising women who are or may be pregnant to reduce their caffeine intake. This is because during the second and third stages of pregnancy, women metabolize caffeine about twice as fast as when they are not pregnant. Moreover, caffeine crosses the placenta into the fetus and flows into the baby through breast-feeding. In addition, many studies have failed to prove that moderate amounts of caffeine have adverse effects on fetuses, and there are no medical reports banning pregnant women from drinking coffee. It is still recommended that pregnant women and breast-feeding women should be more cautious about their caffeine intake. In short, if you find that you are not feeling well after drinking coffee, you should not drink coffee for the time being, and then start with a small amount, changing the way you drink it, and so on.

seven。 The best way to taste coffee is to drink black coffee.

A: there is a saying that if you know how to drink "black coffee" without cream and sugar, you are the expert at tasting coffee. In fact, there is no fixed and correct way to drink coffee, such as coffee from Middle East or African countries, and it also features the addition of cinnamon, ginger and other fragrant families. In the case of a good cup of coffee, black coffee can indeed enjoy its original balanced and rich flavor, while cream can remove some astringency, while adding sugar can turn bitterness into sweetness. In a word, whether or not to add milk or sugar depends on your personal preference. Choose your favorite coffee and you can enjoy it.

eight。 Why can you feel a little sweetness when tasting black coffee?

A: most people only taste bitter, sour and astringent coffee. In fact, raw coffee beans contain about 50.8% sugar. After baking at high temperature, most of the sugars will be converted into caramel. This caramel action brings a unique tea brown to the coffee, forming a source of aroma and bitterness, while the remaining sugar leaves some sweetness. In addition, the tannic acid released when roasting good coffee beans, combined with the formation of brown caramel, will also produce a slightly bitter sweetness.

nine。 Is drinking coffee addictive?

A: caffeine in coffee is a stimulant of the central nervous system. A cup of brewed coffee contains 95 milligrams of caffeine, instant coffee contains 65 milligrams, and decaffeinated coffee contains only three milligrams.

Coffee affects glucose metabolism in the brain, which brings a variety of behavioral effects. At a concentration of one milligram per kilogram, coffee increases activity in several parts of the brain, which control mood and sleep.

If it is increased to three to five milligrams per kilogram, coffee begins to affect other divine areas of the brain, especially the amygdala, which controls a person's degree of anxiety and also affects motor nerves. Niehlig's experiment is an absorbed concentration, so it's a very high concentration.

Niehlig's experiment found that when the concentration of caffeine was increased to 5 mg / kg, the nucleus accumbens did not show any activity. However, when the concentration was increased to 10 mg / kg, the activity of the ipsilateral nerve increased significantly, but at this concentration, every part of the brain was quite excited. Therefore, caffeine has no specific effect on the nucleus accumbens. Other abuse can cause addictive drugs to specifically affect the nucleus accumbens at low concentrations. So caffeine is not addictive.

Although pharmacology proves that drinking two or three cups of coffee a day is not addictive. But many people will say, "I just can't stop drinking coffee!"this is a psychological effect. Drinking coffee has become a habit, and drinking one or two cups of coffee a day can often cheer you up and make you feel good, because coffee is really a brain stimulant.

Drinking coffee has become a habit. If you want to change it for a while, there will be addictive changes, and you will feel headache, irritability or laziness. If you really want to reduce or stop drinking coffee, it's best to take your time and mix caffeinated and decaffeinated coffee from more to less, and eventually to decaffeinated coffee (decaf). A cup of decaf contains only three milligrams of caffeine.

ten。 Why did Christians used to regard coffee as evil?

A: in Penesia in 1615 AD, there was a debate among Christians in Europe because coffee was introduced by Islam. King Clement VIII said: "this demonic drink is so delicious that it would be a pity if it was only enjoyed by pagans!" After that, Christians began to really accept coffee as a drink.

eleven。 When can only men enter the coffee shop?

A: a long time ago, English gentlemen regarded coffee as a necessity for social occasions, and only men could enter the coffee shop at that time. They talk about politics and do business in the coffee shop, and some men even don't go home. As a result, British women launched a petition in 1675 to close the coffee shop.

twelve。 Why do some coffees taste sour?

A: whether coffee tastes sour or not is mostly due to the variety of coffee, some of which have high acidity, such as Kenya, Mocha, Colombia, Guatemala and Costa Rica.

The degree of roasting is also related to the acidity of the coffee, usually the lightly fried coffee beans also contain organic acids, so the coffee washed out tastes sour, while the deep-fried coffee beans, because the high temperature of the fried beans has released the organic acids contained in the coffee beans, so the acidity of the coffee is low. The reason why the coffee will be sour is that the coffee is stirred too many times during brewing or the brewed coffee stays on the heat preservation plate for too long.

thirteen。 What is the "three original species" of coffee?

A: among the many plants on earth, there are at least 40 species of coffee, but the more practical cultivated species are the three original species, namely Arabica species. Robusta species. Liberia card species, and now this order is the order of their quality. The Arabica species has the best fragrance, and its caffeine content is only half that of the Robusta species. At present, the Arabica species account for about 70% to 80% of the world's total output, while the Robusta species are heat-resistant. It is rainy. Less rain, strong adaptability, low cost, output also has 20% to 30% of the total output. Liberia card is not popular except in producing countries and a small number of Europeans because of its poor aroma and bitter taste.

fourteen。 Can pregnant women drink coffee?

A: in 1980, the US Food and Drug Administration (FDA) issued a statement advising women who are or may be pregnant to reduce their caffeine intake. However, many studies since then have indicated that there is no evidence to show that a moderate amount of caffeine has an adverse effect on the fetus, and there is no medical report banning pregnant women from drinking coffee.

However, FDA does not change its original advice, because pregnant women metabolize caffeine about twice as fast in the second and third trimester than when they are not pregnant, and caffeine will cross the placenta into the fetus and into the baby through breastfeeding, so it is recommended that pregnant women and mothers should be as careful about their caffeine intake.

fifteen。 Can you get rid of alcohol with coffee?

A: yes, coffee can really relieve alcohol, this is because coffee has a stimulating effect, it has the same effect as tea.

sixteen。 Does coffee really hurt your stomach?

A: if you don't have any stomach problems, drinking coffee can promote digestion, but if you already have stomach problems, it's not suitable, because coffee irritates the stomach. Patients with gastritis and stomach ulcers should avoid drinking too strong coffee.

seventeen。 Do you brew iced coffee with iced beans or iced beans with ice?

A: iced coffee is made from coffee beans. It is most appropriate to add ice after cooling (at room temperature). If ice is added to cool the coffee, if the ice melts too much in the coffee, the coffee becomes too thin.

eighteen。 What does coffee have to do with water?

A: there are many kinds of water, mineral water, tap water, spring water, stream water, sea water. Which kind of water is most suitable for making coffee? The moisture is hard water and soft water. Hard water makes the brewed coffee non-bitter, because it removes the tannins from the coffee, so it's better to use soft water to make coffee.

About 98% and 99% of a cup of coffee is water, so make good coffee and make wine. Just like making tea, good water quality can show the aroma of coffee. So does the more delicious mineral water match the coffee? Since mineral water is mostly hard water with high contents of sodium, manganese, calcium and magnesium, hard water will hinder the release of caffeine and tannin, which greatly reduces the taste of coffee. In addition, to avoid using water with disinfectant odor, you can use water that is boiled for the second time, and water that has just flowed out of the faucet early in the morning, and the most suitable for brewing coffee should be boiled water boiled on a gas stove. There is still a little carbon dioxide in this boiled water, which can highlight the delicacy of coffee.

nineteen。 How do you taste coffee?

A: drinking coffee should be like tasting a cup of wine. Only through careful taste can you appreciate its essence.

No matter how you brew out the coffee, you don't have to rush into it. First smell the original aroma of the coffee, then take a small sip to try the original taste, then add the right amount of sugar according to your preference, and stir with a small spoon, taking advantage of the stirred coffee whirlpool, slowly add cream to float on the coffee, on the one hand, keep warm, on the other hand, the heat of coffee can also evaporate the smell of milk.

twenty。 Why can black coffee without sugar feel a little sweet?

A: most people think that coffee beans only taste bitter. Sour。 There are three kinds of astringent beans. in fact, raw coffee beans contain about 5% to 8% sugar. after baking at high temperature, most of the sugars will be converted into caramel. this caramelization brings a unique tea brown to the coffee, forming the source of aroma and bitterness. The remaining sugar leaves a slight sweetness. In addition, when roasting good coffee beans, the tannin released and the brown caramel combine to produce a slightly bitter sweetness.

twenty-one。 How to choose a coffee cup?

A: the coffee cup is also one of the necessary equipment for tasting coffee. It is also fun to try to change all kinds of cups according to the situation. The temperature of the coffee cup is one of the key points to determine whether the coffee tastes good or not. The most appropriate drinking temperature is 185 ~ 190 degrees Fahrenheit. Therefore, it is necessary to inject hot water into the warm cup. If you let the coffee cool, it will only highlight the bitter taste.

Types of coffee cups:

1. Standard specification (Standard) 120~140cc, mainly used for black coffee.

two。 Morning 160~180cc, mainly used for mixed coffee.

3. Small coffee cup (Demi-tasse) 60~80cc, mainly used for espresso.

4. The mug (Mag-cup) is 1.5 times as large as Standard and is used for American coffee.

5. Large bowl (Cafe au lait bowl), mainly used for milk coffee.