How to Make Cold Drip Coffee at Home: Coffee-to-Ice Ratio, Grind Size, and Single-Origin Bean Recommendations

What is Cold Drip Coffee?

Cold drip coffee has a light fermented aroma and a richer mouthfeel compared to pour-over coffee. Since cold drip coffee is extracted over a long period and then fermented in the refrigerator, friends who want to order cold drip coffee at FrontStreet Coffee need to make reservations in advance.

Some people say that cold drip coffee tastes better when consumed at a coffee shop. Is it because their homemade version isn't good, or is there another reason? Is there a clear standard? FrontStreet Coffee believes that there's no fixed standard for making cold drip coffee—everyone has their own methods and standards. However, there are some details to pay attention to during the process.

What is Cold Drip Coffee?

Cold drip coffee originated in Europe. Since the coffee distillation apparatus was invented by the Dutch, some call it Dutch Coffee, distilled coffee, or water-drip coffee. As early as the 17th century, Dutch people were already drinking this type of coffee. With the expansion of Dutch colonialism, this coffee was introduced to Korea and Japan, where it became popular. That's why it's also called Dutch coffee.

Cold drip coffee leverages the compatibility between coffee itself and water, primarily using the natural osmotic pressure of condensed water at low temperatures, taking about 8 hours to extract drop by drop. It's a coffee that brews with time, and different water temperatures produce different flavors. At low temperatures, the astringent substances in coffee are less likely to dissolve. Long extraction with ice water, followed by fermentation in the refrigerator after extraction, gives cold drip coffee a light fermented aroma and a richer mouthfeel. FrontStreet Coffee thinks: you can put the coffee in the refrigerator at night and drink it the next morning for instant refreshment! Isn't that a wonderful feeling?

Because cold drip coffee doesn't undergo heating and involves long extraction periods, many flavor molecules are extracted but not fully released. Therefore, after cold drip extraction is complete, it's placed in a sealed bottle in the refrigerator for 12-24 hours, allowing carbon dioxide pressure to build up and release the flavor molecules. This is why cold drip coffee becomes richer the longer it stays in the refrigerator. Extraction with ice water reduces the acidity in coffee, creating a red wine fermentation flavor. The taste is smooth and mellow, with balanced acidity and bitterness, good aftertaste, and is gentle on the stomach. It has low caffeine content and can extract the rich mouthfeel and complete aroma of coffee beans.

During the cold drip coffee production process, tannic acid barely breaks down in cold ice water. Although caffeine decomposes slightly in ice water, it's about 90% less than hot water extraction, while other main components of coffee remain intact. Because cold drip coffee has absolutely no astringency and minimal bitterness, the mouthfeel appears particularly pure.

FrontStreet Coffee's Cold Drip Coffee Details

FrontStreet Coffee wants to share some important details about making cold drip coffee, such as: coffee bean selection, grind size, powder-to-water ratio, drip rate, and storage/shelf life. FrontStreet Coffee's cold drip tower consists of six parts: upper pot, lower pot, adjustment valve, coffee filter cup, snake-shaped conduit, and all-wood stand.

1. Coffee Beans

Cold brew and cold drip both belong to low-temperature coffee brewing methods, where the temperature of water contact with coffee grounds is controlled between 0-7°C. The benefit of low-temperature extraction is that it uses the principle of low extraction efficiency to reduce the release of large-molecule bitter substances, which is why the cold drip coffee we drink is refreshing with rich sweet and sour flavors. Coffee beans are the most important factor—different coffee beans produce completely different cold drip flavors. Therefore, choosing the right coffee beans is crucial for making cold drip coffee. Generally, lightly roasted coffee beans are preferred for cold drip coffee, as the sweet and sour fruity flavors are more comforting at cold temperatures. Some coffee beans with more distinct and special flavors are also very suitable for cold drip coffee. For example, FrontStreet Coffee's Honduras Sherry coffee beans, FrontStreet Coffee's Costa Rica Giant Rock Blueberry, FrontStreet Coffee's Musician Series, FrontStreet Coffee's Colombia Rose Valley, FrontStreet Coffee's Flower Moon Night, and more.

FrontStreet Coffee recommends choosing coffee beans roasted about 20 days ago for cold drip, as freshly roasted coffee beans release large amounts of carbon dioxide gas. When ice water drips into the ground coffee, the gas continuously releases, causing the coffee layer to easily expand and form channel effects, leading to uneven extraction and significantly diminished coffee flavor.

2. Pre-wetting

Using ice water for "pre-soaking" is actually similar to the blooming process in pour-over coffee, which can improve extraction efficiency and consistency. In cold drip's low-temperature and filtration-based extraction, direct dripping might cause uneven moisture in the coffee layer, with some coffee grounds over-extracted while others don't participate in extraction at all. Pre-wetting in advance can also save production time.

3. Place a Round Filter Paper on the Coffee Grounds

To leave enough pre-wetting breathing space for the coffee and make the extracted coffee flavor more complete and clean, we cover the coffee grounds with a filter paper after leveling them. This increases the contact area between water drops and coffee grounds, ensuring even extraction. When water drops hit the coffee grounds, the surface slowly forms a small pit, and water flows down this pit rather than spreading to the sides. This means the coffee grounds in the entire powder bottle won't be fully soaked, causing insufficient extraction. Adding a layer of filter paper prevents this situation.

4. Grind Size

There are two points to note about coffee grind size. If too coarse, the resistance formed by the coffee layer is small, and water more easily passes through to the lower pot. With cold water's low extraction efficiency, this results in weak coffee with insufficient flavor. Too fine is also not good—as resistance increases, it easily causes blockage and water accumulation, and prolonged soaking brings out bitterness. Therefore, FrontStreet Coffee recommends using a grind size that passes 80-85% through a #20 standard sieve. Choose 85% pass rate for richer flavor, or 80% for a cleaner taste.

This time, FrontStreet Coffee used the refreshing FrontStreet Coffee Kenya Assalia coffee beans. Since extraction rate is low at cold temperatures, FrontStreet Coffee's barista recommends using a slightly finer grind than pour-over. Here we use 85% pass rate with standard sieve, which is 9.5 on the store's EK43S grinder.

5. Importance of Leveling Coffee Grounds

Cold drip coffee must have the grounds leveled. Many people don't understand why cold drip coffee also needs leveling. Here, it's important to note that cold drip leveling isn't about pressing firmly, but first gently tapping the powder to maintain even structure in the filter cylinder, then using a flat tamper to gently level it. Remember to press gently when leveling, not forcefully like espresso extraction. If pressed too firmly, since cold drip coffee doesn't have pressure like an espresso machine for extraction, it easily causes water accumulation in the coffee layer, preventing coffee liquid filtration. Additionally, cold drip filter paper or filter discs are usually at the bottom, unlike coffee filter cups which have ventilation grooves, so when coffee grounds are soaked in water, the exhaust effect is also affected, causing uneven extraction of the entire coffee puck.

6. Control Drip Speed and Powder-to-Liquid Ratio

This is somewhat similar to the pour speed in pour-over coffee. Some people prefer 1 drop per second, others prefer 1 drop every 2 seconds. This directly results in different completion times—the slower the drip, the longer it takes; the faster the drip, the shorter the time. FrontStreet Coffee typically uses 7 drops every 10 seconds for extraction, but everyone can adjust the flow rate according to their preference. The powder-to-liquid ratio is 1:10. Since FrontStreet Coffee serves cold drip coffee diluted with ice cubes, we use a higher concentration. If making at home, you can use 1:12-1:14 for extraction.

FrontStreet Coffee makes cold drip by grinding 60g of coffee beans, placing a round filter paper in the powder cup, pouring in the coffee grounds, then covering with another filter paper on top before wetting the coffee grounds with water. This saves dripping time while avoiding uneven extraction. Fill the upper pot with an ice-water mixture (ice to water ratio of 1:1) to extract a total of 600g coffee liquid.

7. Serve Cold After Refrigeration

Some say that pour-over coffee should be drunk immediately and finished within a certain time, as it becomes more irritating and unpleasant if left too long. What about cold drip coffee? Freshly made cold drip coffee can be consumed immediately, but FrontStreet Coffee recommends refrigerating it for 12 hours before drinking. This allows the cold drip coffee's flavor to reach its best. The process of pouring into glass bottles helps mix coffee liquids of different concentrations, while choosing well-sealed containers ensures no external contamination. Although refrigerators may appear clean, they actually contain many microorganisms invisible to the naked eye. Placing in the refrigerator for 12 hours of low-temperature fermentation gives cold drip coffee an aromatic fermented fragrance, while the original flavors also become richer. Fermentation is very common in daily life, but uncontrolled fermentation leads to food spoilage. Low-temperature environments effectively slow this process, and FrontStreet Coffee has verified that most cold drip coffees made from various beans taste best after 12 hours of refrigeration.

Just as the cold drip coffee FrontStreet Coffee makes at a 1:10 ratio is very concentrated, FrontStreet Coffee adds 40g/200ml of ice cubes when serving, diluting it while maintaining the chilled effect.

How Does FrontStreet Coffee's Cold Drip Taste?

At FrontStreet Coffee, baristas typically blend two types of coffee to make cold drip in order to better highlight and balance the flavors of each cold drip coffee. The goal is to emphasize certain flavor characteristics—one bean provides aroma, while another provides flavor.

20g [FrontStreet Coffee Honduras Lychee Lan] + 40g [FrontStreet Coffee Geisha Village Red Label]

Barrel-processed FrontStreet Coffee Lychee Lan plus natural-processed FrontStreet Coffee Geisha Village Red Label, with a light brandy fragrance, plum-like acidity paired with maple sweetness.

FrontStreet Coffee's brandy barrel-processed Lychee Lan has rich brandy aroma, chocolate finish, and honey aftertaste.

FrontStreet Coffee's natural-processed Geisha Village Red Label has plum and citrus fruit acidity, with maple sweetness and a creamy smooth mouthfeel. When made into cold drip, you'll experience a light brandy aroma, rich fruit acidity leading to honey sweetness and a creamy smooth texture.

FrontStreet Coffee's Brewing Suggestions:

Regardless of what type of coffee you're brewing, the freshness of coffee beans is very important. FrontStreet Coffee has always believed that coffee bean freshness greatly affects coffee flavor, which is why FrontStreet Coffee ships all coffee beans within 5 days of roasting. FrontStreet Coffee's roasting philosophy is "Freshly Roasted Good Coffee," ensuring every customer receives the freshest coffee when they place an order. The coffee resting period is about 4-7 days, so when customers receive their coffee, it's at its peak flavor.

For friends who need ground coffee, FrontStreet Coffee kindly reminds you: pre-ground coffee doesn't need further resting, because during transportation, the pressure from carbon dioxide in the packaging also helps round out the coffee flavor, so you can brew a cup immediately upon receiving the ground coffee. However, ground coffee needs to be brewed promptly, as it oxidizes quickly when exposed to air, meaning the coffee flavor will dissipate more rapidly and won't be as good. Therefore, FrontStreet Coffee recommends buying whole beans and grinding fresh for each brew to better appreciate the coffee's flavor.

Brewing coffee is also an art, and FrontStreet Coffee believes that with more practice, you can also make delicious cold drip coffee at home.

For professional coffee knowledge exchange and more coffee bean information, please follow Coffee Workshop (WeChat official account: cafe_style).

For more specialty coffee beans, please add FrontStreet Coffee's private WeChat account: qjcoffeex

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473