Making cold brew coffee can be said to be the easiest among all the many coffee extraction methods and requires no technical skill at all—it's a way for every coffee novice to easily brew a delicious iced coffee. Front Street has shared quite a few articles about various aspects of cold brew knowledge and has conducted comparisons and experiments of all sizes on the various parameters involved. Not long ago, however, a friend posed a question to Front Street: Can espresso-ground coffee be used for cold brew?

What are the characteristics of cold brew coffee?

Cold brew coffee tastes good because soaking in low-temperature water makes it harder for undesirable substances in the coffee to be released (such as bitterness, astringency, etc.), while it can fully extract the pleasant substances (such as fruity acidity, sweetness, and other flavors). Therefore, compared with other coffees brewed with hot water, cold brew coffee is cleaner, has a rounder mouthfeel, and a fuller taste.

If we were to name the drawbacks of cold brew coffee, Front Street thinks there are two issues. One is that its production time is relatively long, usually requiring 8–12 hours of soaking in the refrigerator. However, Front Street believes that good coffee is worth waiting for~ You can soak it before going to sleep at night, then simply filter it the next morning and drink a cup of energizing cold brew coffee!

Andthe other aspect is that if the coffee beans are not chosen correctly, cold brew can easily develop negative flavors, ultimately making the coffee taste like a cup of Cantonese herbal tea. So in addition to controlling the various parameters well, choosing coffee beans that suit your own taste is equally important.

What coffee beans are recommended for making cold brew coffee?

Cold brew, cold brew—as the name suggests, it is an iced drink. If we choose dark-roasted coffee to make it, the resulting coffee liquid will most likely have an icy yet bitter taste. At the same time, because there is no support from high temperature, the bitterness will linger and not dissipate, making people not want to take a second sip after the first. So when making cold brew at home in daily life, Front Street first recommends light-to-medium or medium-roast coffee beans with more prominent aromas or more obvious sweet-and-sour notes. The iced coffee made this way is not only suitably sweet and sour, but also has a fresh, cool juice-like quality, especially suitable for summer.

For example, the "Ethiopia Natural Alo Village Coffee Beans" currently sold by Front Street Coffee have a light floral aroma, full berry-like sweet acidity, and at the same time a moderate fermented note and a black-tea-like sweet aftertaste; or the "Panama Butterfly Coffee Beans," which have bright citrus acidity, fresh white floral notes, honeyed sweetness, and a green-tea-like sweet aftertaste; and also the "Honduras Sherry Coffee Beans," which have a whisky-like aroma, a vanilla cream cake-like sweet smoothness, and a nutty caramel finish, leaving an endless aftertaste after drinking.

The water-to-coffee ratio for making cold brew and an explanation of the steps

The ratio for making cold brew coffee is 1:10–1:12. For example, for 30g of coffee grounds, we usually use 300g of cold water for soaking.

In terms of grind size, Front Street Coffee recommends using coffee grounds with a texture like fine granulated sugar (75% passing through the Chinese No. 20 standard sieve). If you don't have a grinder at home, you can note "grind for cold brew" when placing your order~ Front Street needs to emphasize that after grinding, the coffee aroma will dissipate faster, so if conditions permit, it is still recommended to grind and brew fresh.

To make cold brew coffee, choose a clean, sealable container, then pour in the coffee grounds and an appropriate amount of water, stir a little so the coffee grounds and water fully contact, then seal it well and put it in the refrigerator to chill for 8–12 hours.

When the extraction time is about right, take it out and use a filtering tool to filter it, then pour it into a clean, sealed container and store it in the refrigerator. After filtering out the grounds, cold brew coffee can usually be kept for about 5 days, and during this period it must be drunk as soon as possible.

Can espresso-ground coffee be used for cold brew?

Let us get back to the point and return to the situation mentioned by the friend at the beginning. The reason this question was raised is that the grind size of the coffee grounds does not meet our cold brew extraction requirements.

We all know that the grind size generally used for making espresso is as fine as flour. Therefore, when water is added according to the above ratio and then soaked for a long time, it will release soluble substances more easily than a regular grind size (fine granulated sugar level), ultimately making the coffee both strong and bitter, and even astringent. So in order to avoid over-extraction, we need to make adjustments in two details: the soaking ratio and the time.

Here, Front Street uses Papua New Guinea Bird of Paradise as a demonstration. This bean is presented as a medium roast. When pour-over brewed, its flavor shows creamy nuts, cocoa, and a clear sugarcane sweetness. It is suitable for a variety of brewing methods and is a relatively versatile single-origin coffee.

In order to reproduce the situation everyone encounters, Front Street used the Galileo Q18 espresso grinder used in the shop and adjusted the setting to 2.5 for grinding suitable for pulling espresso. To the naked eye it looks as fine as powdered sugar, and when rubbed with the fingers you can feel fine particles.

Since the coarseness of the coffee grounds is already fixed, if we want to reduce the extraction rate, we must first shorten the time the water soaks the coffee grounds, and second increase the coffee-to-water ratio, that is, change the coffee concentration, thereby making the flavor lighter. The specific parameters are as follows:

Coffee grounds: 50g

Coffee-to-water ratio: 1:13

Cold water: 650g

Soaking time: 3 hours

After filtering: refrigerate for another 2 hours

Because the coffee grounds are finer, the water flow meets greater resistance during filtration, so it takes longer. The coffee liquid just after filtering, because the flavor substances are stillsuspended in the water,usually tastes a bit powdery. We can first seal it and put it in the refrigerator for a short period of chilling to let the suspended substances settle slightly, thereby making the coffee's mouthfeel cleaner.

In addition, considering that espresso-ground coffee is mostly dark-roasted, with flavors dominated by caramelized aromas, a thick mouthfeel, and slightly heavy bitterness, if you pursue a refreshing taste, Front Street suggests adding a few ice cubes after filtering before tasting.

With the support of ice cubes, today's cup of Bird of Paradise cold brew tastes of spices, almonds, and caramel, while also carrying an oolong tea note. The acidity is relatively weak, the mouthfeel is icy and refreshing, and the energizing effect is excellent.

But if the espresso-ground coffee you bought is on the darker-roasted side, the cold brew soaked from it may be relatively thick and heavily bitter. In the spirit of not wasting anything, you might as well try pairing it with other ingredients. First, it will be easier to drink, and second, it can add flavor. For specific instructions, you can refer to this article: "A different approach! Multiple hidden ways to drink cold brew".

The above content is compiled by CoffeeHunters, a coffee news website.