What is Cold Brew Coffee?
Cold brew coffee is coffee that is extracted at low temperatures. It is often confused with iced coffee, which usually refers to coffee that is cooled with ice cubes after being extracted at high temperature. So the first and biggest difference between iced coffee and ordinary iced coffee is the extraction temperature.
if the same type of coffee beans are used, what is the difference in taste at different extraction temperatures? ?
The biggest difference is that the chemical reaction of coffee beans will be different at low temperature, which will reduce the sour and bitter taste that can only be formed at high temperature. The masked fruity and bean flavors are more prominent, making the flavor pure. If the extraction time is long enough, the mellow aroma of the wine will be produced due to slight fermentation, making the flavor more mellow and long-lasting.
The second most important difference is the extraction time. Cold brew coffee generally takes 12 to 48 hours to extract, which is much longer than coffee extracted at high temperatures. This is because the extraction speed of the flavor will be slower at low temperatures Slow, so there is enough time for the coffee liquid to ferment.
Since the cold brewing method directly increases the production cost, if there is no special label, the iced coffee that can usually be drunk in the beverage store is ordinary iced coffee, not cold brewed coffee.
Is Cold Brew Coffee Healthier?
Because of its low acidity, cold brew coffee is less likely to hurt the stomach, so it is more suitable for people with sensitive stomachs. In addition, in the general perception, cold brew coffee may have lower caffeine, because coffee beans release less caffeine at low temperatures. But it is not.
A 2017 study pointed out that for coffee extracted at low temperature (21-25oC), the concentration of caffeine of different coffee beans will be different from that extracted at high temperature (98oC) as long as the extraction time is about 400 minutes. A 6 minute coffee is about the same, if not higher. The reason is that low temperature only affects the rate of caffeine extraction, making it slower, but has little effect on solubility.
Fuller, M., & Rao, N. Z. (2017). The Effect of Time, Roasting Temperature, and Grind Size on Caffeine and Chlorogenic Acid Concentrations in Cold Brew Coffee. Scientific reports, 7(1), 17979. https://doi.org/10.1038/s41598-017-18247-4
Since the making process of cold brewed coffee is usually longer than 400 minutes, the caffeine concentration of cold brewed coffee is almost higher than that of other coffees. If you are a friend who cannot or does not want to drink too much caffeine, you must pay attention to cold brewed coffee The amount of coffee consumed.
The Secret to Cold Brew Coffee
To make a successful cold brew coffee, the variety of coffee beans, degree of roasting, degree of grinding, quality of water, equipment, etc., are all very important. But the most important secret is to have patience, because the flavor and aroma of coffee will only be fermented long enough to develop.
When you've almost forgotten about it, that's when your cold brew is done. Sometimes in order to get a more mellow taste and slightly fermented wine aroma, the finished cold brew coffee is kept in the refrigerator for a day or two before it reaches the peak of flavor!
How to Make Cold Brew at Home
The following will introduce the practice of cold brew coffee, which can be divided into lazy method, super lazy method and ultimate lazy method.
Lazy Method
Coffee beans/powder: You can buy coffee bean powder or grind coffee powder yourself. It is recommended to use light-medium roasting for coffee beans. The grinding degree of coffee powder is medium-fine. If you like sweet and sour, choose washed beans, and if you like fruity aroma and strong wine aroma The optional honey treatment and solarization.
Ratio: Add coffee powder to the container and add ice water, the ratio of coffee powder to water is 1:10 to 1:15. For example, 20g of coffee powder is added to 200ml of water. When drinking with ice cubes or milk, it is recommended to drink at a ratio of 1:10, and to drink directly at a ratio of 1:15.
Time: Seal the container and put it in the refrigerator for 12 to 48 hours. The longer the time, the thicker it will be.
Filtration: Finally, use filter paper to filter the coffee powder before drinking. The filter paper should be rinsed with water first to prevent the smell of the filter paper from mixing into the coffee.
Super Lazy Method
If you think it is too troublesome and inconvenient to use filter paper to filter every time you make cold brew coffee, you can put the coffee powder into a non-woven filter bag, put the coffee powder into a glass bottle like making tea, and put it in the refrigerator Wait patiently, and finally take out the coffee powder bag and drink it directly.