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The flavor of pour-over coffee is always delicious, of course, you need to get some details right. Maybe it's time to change things up—then how about a cup of cold drip coffee! Front Street's cold drip coffee has always been very popular, especially in the hot summer, a cup of cold drip coffee is simply the best! Of course, in this cool weather, a cup of cold drip is also very refreshing!
Cold drip coffee, as the name suggests, is coffee brewed with low-temperature water. The pour-over coffee we usually drink is brewed with high-temperature water—these two are completely different operations! The advantage of high-temperature extraction is that it can quickly extract the flavor substances from the coffee, causing the tannic acid in the coffee to rapidly break down into pyrogallic acid, producing sourness, sweetness, and bitterness—this is what Front Street often calls the process of releasing coffee flavor. The disadvantage of high-temperature extraction is that it easily causes the coffee flavor to be fully released, and then it starts to release the flavor of the coffee bean's woody fiber—what we commonly call off-flavors, woody notes, and other unpleasant tastes.
Low-temperature coffee extraction uses near-zero-degree ice water for extraction, allowing the coffee's flavors to reduce volatilization under low-temperature conditions, preserving the coffee aroma in the coffee liquid as much as possible. When it enters your mouth, as the coffee liquid temperature rises, the aroma contained in the coffee liquid suddenly bursts out, letting the coffee drinker feel an intense aroma at the back of the tongue. This sudden aroma burst creates a great sense of happiness. The downside is that it takes a long time to make, and the cold drip coffee cannot be drunk immediately after dripping—it needs to be placed in the refrigerator and left still for more than 8 hours, so that the flavor molecules extracted at low temperature can be fully released.
So where did cold drip coffee come from?
According to Front Street's understanding, cold drip coffee was invented by the Dutch, so it is also called Dutch-style drip coffee. Unlike other brewing methods that require hot water, cold drip coffee is characterized by using ice water to extract coffee. Low-temperature extraction requires a longer time to dissolve the aromatic substances in the coffee. So it uses a dropper similar to a chemistry experiment, letting ice water drip drop by drop, slowly infiltrating and penetrating through the coffee grounds. In the traditional cold drip coffee maker commonly seen, the dripping speed of the water drops can be controlled. Cold drip coffee is also called water drip coffee or ice-brewed coffee. It is a method of making coffee drinks, and the common cold coffee drip filter consists of 3-4 layers of glass containers mounted on a wooden stand.
What is the extraction principle of cold drip coffee?
Pour-over coffee is brewed using a specified high water temperature, time, and coffee-to-water ratio—simple and quick. Cold drip coffee, however, is a coffee brewed with time. We know that coffee brewed with different water temperatures will taste different, and at low temperatures, the astringent substances in coffee are less likely to dissolve out. Using ice water for long extraction, after extraction is complete, it is placed in the refrigerator for fermentation. The slightly fermented cold drip coffee has a faint fermentation aroma, and the mouthfeel tends to be fuller. Since it is not extracted at high temperature, fewer impurities are extracted from the coffee, and the caffeine content is slightly lower. For those who are affected by caffeine, Front Street suggests choosing cold drip coffee—it's not as harsh on the stomach, and the caffeine is relatively lower, while the coffee flavor layers are also very rich!
What kind of coffee beans are suitable for cold drip coffee?
We know that pour-over coffee has relatively broad requirements for coffee bean selection—almost any coffee bean can be used for pour-over. Of course, different roast levels require slightly different brewing methods. Espresso has certain requirements for coffee bean selection, for example: it requires a darker roast than pour-over coffee beans, meaning the coffee beans need to be medium-dark roasted; otherwise, the espresso flavor might be hard to accept. Of course, if you like light-roasted beans for espresso, then there's nothing more to say.
What about cold drip coffee? What coffee beans are more suitable? Generally speaking, pour-over coffee beans can all be used for cold drip coffee. Actually, Front Street believes that making cold drip coffee mainly depends on what flavor you personally prefer. However, Front Street still thinks single-origin beans are best for cold drip coffee—effectively removing bitterness and tannic acid, with a rich and smooth mouthfeel, not sour or astringent, and not harsh on the stomach. Sometimes we also use two or more single-origin beans to make cold drip. Compared to cold brew coffee, cold drip coffee has more aroma, and the taste is more delicate and subtle.
Since cold drip coffee uses a longer period of cold water penetration extraction, Front Street suggests choosing coffee beans with more intense flavors for cold drip, such as Kenya, Yirgacheffe, and other strongly charactered beans. The coffee extracted this way will be very distinctive.
Below is a share of the cold drip coffee recipes that Front Street Coffee often makes.
1. Dark berry type: Costa Rica Mozart 60g,The Mozart coffee bean uses an anaerobic honey processing method and itself has a very special raisin aroma. Used for making cold drip coffee, it exhibits very obvious blueberry, black grape, and wine-fermented flavors, with a refreshing mouthfeel and lingering fragrance on the palate.
2. Refreshing and clean type: Kenya Asalia 60g. Asalia's acidity is very lively, like a glass of juice overall. Used for making cold drip coffee, it carries the fresh fragrance of cherry tomatoes and grapefruit, with a refreshing and light acidity—very suitable for summer drinking.
3. Sweet and delicious type: Indonesia Golden Mandheling 60g. Few shops use dark-roasted coffee to make cold drip coffee. If you haven't tried it, you might think cold drip made from dark-roasted coffee beans would be very bitter—but actually it's not like that. Using Front Street's cold drip method and placing it in the refrigerator for 24 hours before adding ice cubes, the Golden Mandheling cold drip coffee presents as sweet, with a hint of chocolate bitterness, very clear overall, and a rich fermented aroma that makes you feel comfortable.
Front Street blended bean cold drip coffee recipe:
In order to make each cold drip coffee's flavor more prominent and balanced, baristas usually use two coffees blended together to make cold drip. The purpose is to make this coffee more prominently highlight a certain flavor characteristic—one bean provides aroma, one bean provides flavor.
For example:
20g [Front Street Coffee Honduras Litchi Orchid] + 40g [Front Street Coffee Gesha Village Red Label]
Wine-barrel-processed Litchi Orchid plus sun-dried Gesha Village Red Label—a faint brandy aroma, plum-like acidity paired with the sweetness of maple syrup.
The brandy-barrel-processed Litchi Orchid has a rich brandy aroma, with chocolate in the finish and a honey aftertaste.
Sun-dried Gesha Village Red Label—plum and citrus fruit acidity, with the sweetness of maple syrup and a creamy, smooth mouthfeel.
Made into cold drip, you will feel a faint brandy aroma, with rich fruit acidity leading the honeyed sweetness and creamy smooth mouthfeel.
This time Front Street will use Costa Rica Mirazu Estate Gesha blend and Honduras whiskey-barrel-fermented Sherry to make iced coffee for demonstration.
1. Place a circular filter paper at the bottom of the powder cup, wet it with water to adhere to the cup wall, add 60g of ground coffee powder (Front Street Coffee uses the Chinese standard No. 20 sieve, with a 58% passing rate, just a little coarser than the pour-over grind size), then shake it flat. You can also use the weight of the tamper to lightly press the coffee layer to make the surface flat.
2. Lay a piece of filter paper on top of the coffee powder layer. Because the tension of the filter paper allows water to evenly distribute across the surface of the coffee powder layer for extraction. Without the filter paper, prolonged dripping would create a pit in the coffee bed.
3. Use ice water for "pre-infusion," evenly moistening the entire coffee powder layer with ice water. This step is like the blooming stage of pour-over coffee, which can improve extraction efficiency and consistency of the final product.
4. Put a 1:1 ice-water mixture into the water container, and adjust the valve to about 7 drops per 10 seconds.
5. After making it, pour the coffee liquid into a sealed glass bottle and place it in the refrigerator to mature overnight, allowing the coffee flavors to blend together, resulting in a better taste that is easier to drink.
Pour-over coffee or espresso can be enjoyed immediately after making. Is cold drip coffee the same? The answer is: no.
After cold drip coffee finishes dripping, it needs to be placed in the refrigerator to ferment for more than 12 hours. Why? Front Street believes this is an oxidation process. Just like coffee beans that have just finished roasting—about 2% of their weight is carbon dioxide, and this large amount of carbon dioxide is released depending on the storage environment, equipment, or method, making the pressure inside the packaging higher than one atmosphere. The pressure helps the aromatic substances and oils merge, allowing all the aromatic substances inside the coffee bean to reach a state where they are easily extracted.
Cold drip coffee is the same—due to the long extraction time, many flavor molecules have been extracted but not well released. So after cold drip coffee extraction is complete, put it in a sealed bottle in the refrigerator and let it sit still for 12-24 hours, allowing the carbon dioxide pressure generated inside the bottle to release the flavor molecules. This is also why the longer cold drip coffee sits in the refrigerator, the richer it tastes. Of course, it's not that you can leave it as long as you want—Front Street does not advocate leaving cold drip for a week. After all, there are bacteria in the air or in the bottle, and it's hard to guarantee the coffee's condition after sitting for a long time. The recommended drinking period for cold drip is within 72 hours. Don't feel it's a waste if it's been over 72 hours—coffee left that long might not be good for your health.
Front Street coffee brewing suggestions:
Whether it's pour-over coffee, espresso, or cold drip coffee, Front Street believes that the freshness of coffee beans is the most important thing, because the freshness of coffee beans directly affects the coffee's flavor. The coffee beans shipped by Front Street Coffee are all within 5 days of roasting, because Front Street deeply understands the great impact of coffee bean freshness on flavor. Front Street's roasting philosophy is "Freshly roasted good coffee," so that every customer who places an order receives the freshest coffee when they get it. The resting period for coffee is about 4-7 days, so when customers receive it, it's at its optimal flavor.
Of course, some customers need Front Street to help grind the coffee. That's also fine, but Front Street must remind you: once coffee beans are pre-ground, they no longer need resting, because during transportation, the pressure generated by carbon dioxide inside the packaging can also make the coffee flavor rounder. So when you receive the coffee grounds, you can immediately brew a cup and drink it. However, coffee grounds need to be brewed promptly, because coffee grounds oxidize relatively quickly after contacting air—meaning the coffee flavor will dissipate faster, and the coffee won't taste as good. Therefore, Front Street recommends buying whole beans and grinding fresh before brewing, so you can better enjoy the coffee's flavor.
The above content is compiled by CoffeeHunters, a coffee news website.
