Cold iced coffee, which looks very expensive, not only relieves summer heat, but also is easy to make.

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As the temperature continues to soar, cold coffee has become popular again, becoming a new summer favorite of friends. Cold extracted coffee, which looks like deiced American coffee and ice coffee, how does it attract everyone, and why is it so expensive?

The flavor of cold coffee

Higher and colder, but softer

Although cold-extracted coffee has become more and more popular in recent years, human beings have a long history of soaking coffee in cold water for a long time. At least as early as the 17th century, the Dutch invented a way to get espresso by soaking coffee powder in cold water for a long time.

With the continuous evolution of the cold extraction process, people gradually realize that the coffee obtained by low temperature and long time extraction will have less acidity and bitterness and lower caffeine than the conventional method.

This is because the water solubility of different flavor substances in roasted coffee beans is affected by temperature differently. Sour acidic fats, large granular molecules produced after baking, and caffeine have lower solubility in cold water and are more difficult to extract. Take Starbucks as an example, with the same coffee ingredients, the coffee obtained by cold extraction has 11% less caffeine than that obtained by American technology.

At the same time, low temperature avoids the conversion of chlorogenic acid in coffee beans by heat, which is the main reason for the bitterness of coke in conventional coffee brewing.

Most of the aromatic substances of coffee beans can still be fully released after extraction for a long time. In this way, the sour and bitter taste of the coffee is lower than that of the conventional way, and the other aromas of the coffee beans are therefore more prominent.

Finally, an important but often overlooked point. Ordinary iced coffee is obtained by rapidly cooling hot coffee with ice cubes, and the process of melting ice inevitably dilutes its own taste. The coffee made by cold extraction is cold itself, even if ice is added before drinking, the dissolution rate is slower, ensuring the concentration of flavor.

Of course, this is not to say that cold extract is a coffee panacea. As a core component of coffee bean flavor, proper acidity is essential. The low acidity of cold-extracted coffee makes many experienced coffee lovers feel that it is not coffee.

In addition, like other processes, the quality of cold-extracted coffee is closely related to the production process. Good cold-extracted coffee needs to be fresh and lively, but also to convey the characteristics of coffee beans. And a long time of patient purchase and gouache proportion of the attempt, but also let the boutique coffee shop cold extraction coffee is much more expensive than ordinary iced coffee.

Ice droplets and cold bubbles

Different aloof and aloof

There are two main methods of cold-extracted coffee: cold bubbles and ice drops. All of them are based on the process of low temperature extraction for a long time, but they still have a lot of attention.

Cold bubble

As the name implies, the ground coffee powder is soaked in cold water or room temperature for 12-24 hours, and then the liquid is filtered. In the whole process, only cold water came into contact with the coffee powder. The variable is relatively small and the taste is relatively stable, so this is also the cold extraction method commonly used by coffee chains.

Ice drop

Ice droplets allow ice water to pass slowly through coffee powder, which requires a special curling kettle to control the speed at about one drop per second. The biggest difference with cold bubble is: on the one hand, the contact time between each drop of water and coffee powder is shorter; second, in the process of ice drop, coffee has more contact with air, and the mild oxidation process will bring some uncontrollable factors to coffee.

Although it usually takes only 5-8 hours for ice droplets to make coffee, you can put the coffee into a smell-free freezer and let it develop steadily overnight, with unexpected aromas.

In theory, ice droplets also belong to cold-extracted coffee, but usually the cold-extracted coffee is made by cold bubbling. if there are ice droplets, the barista is likely to say directly that we have ice-drop coffee.

How to make it yourself

Special equipment is needed to make ice-drop coffee, and there is more room for cold-soaked coffee. After going home in the evening, you can grind the beans and soak the powder in cold water. After about 12 hours, you can drink it by getting up and filtering it in the morning, which is both economical and convenient.

So what are the points worth paying attention to in the process of DIY cold extraction coffee?

First, like hot coffee, the thickness of coffee powder is very important. To put it simply, the finer the powder is, the more bitter it will be, so the extraction time should be shorter; the thicker the powder should be, the longer the extraction time should be, so as not to extract a cup of light dishwashing water. If you're not sure, try breadcrumb-sized coffee powder first.

Second, as mentioned above, the length of extraction is also a major factor, and mainly depends on personal preference. If you like it rich, you can extract it for a long time.

Third, the proportion of coffee powder and water can be controlled by itself, but it is basically higher than ordinary coffee. If you are not sure, you can soak it thicker first, then dilute it with water or add milk and sugar later according to the flavor.

Fourth, cold-extracted coffee has higher requirements for water quality, it is best to use pure water.

About the choice of coffee beans. No matter which flavor you like, do-it-yourself cold coffee will not let you down.

Of course, ice drop coffee requires a special drip kettle, but now it is also very convenient to buy. Some domestic and Nissan brands have affordable household models, with prices ranging from more than 100 yuan to thousands of yuan. In recent years, we have also produced a simple version with fixed flow and convenient assembly and use, so that beginners can make a decent pot of iced coffee at home. The result of the personal test is good, and every time the coffee is made, it is carved up by colleagues.