What affects the taste and flavor characteristics of cold brewed coffee? How long and hours should I brew iced coffee?

Even on cold winter days, many friends will choose to have a cup of cold extract to pass their addiction. Just like eating ice cream in winter, drinking cold extract coffee in winter will give you a different experience. This morning, a friend asked a question related to the production of cold extract when buying beans at Qianjie store: He said that the cold extract coffee he made often suffers from bitter conditions, and asked Qianjie if there were any corresponding improvement plans. The cold extracted coffee we often talk about mainly refers to cold brewed coffee, which is a method of making coffee that steaks coffee powder by standing in cold water for a long time.

Qianjie has shared in previous articles that immersion extraction is not easy to overextract coffee. One is because of the concentration gradient. When the liquid used to soak coffee powder reaches a certain concentration, its extraction efficiency will decrease. As the concentration increases, the extraction efficiency becomes lower and lower. Then, in addition, the production process of cold extract coffee hardly involves much stirring and is left standing most of the time, so the cold extract we make is actually very difficult to extract, and the rollover is more due to the agglomeration of the fine powder and insufficient extraction occurs.

But yes! I am sad that extracting does not mean that it will not be overextracted. Many friends have a distinct bitter, miscellaneous and astringent taste due to improper operation or excessive extraction efficiency. So today, Qianjie is here to share with you what improper operations will allow us to brew bitter, mixed and astringent over-extracted cold extracted coffee!

1. Steaming with hot water/soaking in warm water for cold extraction Generally, the initial water temperature we use when making cold extraction coffee is normal temperature, and then the brewing time will be 8 to 24 hours. However, in recent years, a "evil cultivation" brewing method has emerged, which was shared by Qianjie before, which is to use higher-temperature water to brew cold extract coffee. Steam in hot water, or soak in warm water. The purpose is very simple, that is, to shorten the production time of cold extract coffee.

Since the extraction efficiency of hot water is many times higher than that of water at room temperature, when we use hot water to steam/warm water to brew cold extracted coffee, the extraction time will be greatly reduced. Many friends value this point, so they have learned relevant production. The reason why many cold extract coffees suffer when brewed is related to this "evil cultivation" method. Since the extraction efficiency has been improved, naturally, the macromolecules of coffee that emit bitter and miscellaneous expressions will be dissolved more quickly. If the extraction time and the grinding degree of the coffee powder are not properly controlled, the coffee will be very easy to brew bitter taste.

If you plan to use this method to quickly make a cup of cold extracted coffee, then you must find the right degree of grinding and soaking time of the coffee powder, so that the occurrence of over-extraction can be effectively reduced. If these variables cannot be well controlled, Qianjie's suggestion is that it will be more appropriate to use room temperature water for immersion.

2. Use deep-roasted coffee beans If the coffee beans you use are roasted deeply, there is a high probability that a pot of cold extracted coffee with bitter taste will be easily extracted. In addition to the fact that deep-roasted coffee itself has a charred aroma similar to bitterness, it is also because they have a looser structure and are easier to extract. If the grinding used is too fine or the soaking time is too long, it will be easy to soak out the negative substances in their bodies.

In the same way as the previous case, in this case, it is best for us to avoid over-extraction by adjusting rough grinding/shortening the soaking time. But even so, the cold extract made with deep-roasted coffee will inevitably have a certain bitterness. If you can't accept this taste, Qianjie Association recommends that you choose medium and light roasted coffee beans for making it. For example, among the Front Street coffees, Front Street Essay Huaquai, Costa Rica Strawberry Sugar, and Panama Poquet Rose Summer can all make cold extract coffee with strong fruity and floral flavor ~

3. The soaking time is too long. As Qian Jie said, the advantage of cold extracted coffee is that it is soaked in low warm water and has a high fault tolerance rate. We can not end its extraction by pinching the time like making other coffees. Just take it out and filter it out within about time. But it is precisely because of this characteristic that many friends wantonly extend the soaking time, which in turn leads to the occurrence of excessive extraction.

Generally, the parameters used for soaking cold-extracted coffee in Qianjie are a ratio of powder and water of 1:10, the grinding degree is 75% to 80% of the sieving rate of No. 20 sieve, and the soaking time will be controlled at about 8 to 12 hours with room temperature water. If you feel that you can't take out the cold extract for filtration within this time, the Front Street Conference recommends that you mix it with coarse grinding, so that even if the extraction time is longer, over-extraction will not easily occur.

4. The ratio of powder to water is too large and the coffee is too strong. Some friends said that they made it completely according to the parameters of Qianjie, and they also used lightly roasted coffee, but the coffee obtained was bitter to drink and was not easy to eat. Even if it was coarse and ground, the coffee obtained was not so easy to eat.

In this case, it may not be excessive, but it may just be because the coffee is too strong. The reason why Qianjie uses a powder-to-water ratio of 1:10 is because 90g of ice cubes needs to be added to maintain the low temperature of the coffee when it is produced. The ice cubes will melt while maintaining the low temperature, diluting the coffee, so it is necessary to increase the coffee. The concentration to offset the diluting effect caused by the ice cubes.

If we taste it directly without diluting it, the coffee will probably be difficult to drink and will have a bitter taste as this friend said. But this is not because the coffee is over-extracted, but because the concentration is too high. The solution is very simple. If you have used a ratio of 1:10 to soak the cold extract and confirm that it is too strong after tasting, then you can dilute the concentration by adding ice and water; If you have not started making yet and have no plans to add ice after making, the Qianjie Association recommends using a ratio of 1:12 for making. The cold extract concentration produced by this ratio is just right, and the coffee will be in a good condition to taste.

So these are the four main culprits that make the cold extracted coffee too bitter. If the cold extract you brewed also has obvious bitterness, you may wish to refer to it and see if you have stepped on one of them. If you improve it, you can soak a cup of cold extract coffee that is not bitter ~

- END -

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473