How to Make Cold Brew Coffee: Process Steps, Water Selection, Grind-to-Water Ratio, Time & Grind Size

With the arrival of summer, trendy iced coffee naturally comes to mind. Indeed, in this scorching summer, a cup of iced coffee can instantly make you feel refreshed. Today, FrontStreet Coffee wants to talk about cold brew coffee with everyone. Cold brew coffee has become a favorite among office workers. Why is that? FrontStreet Coffee believes that cold brew coffee is so popular mainly because its preparation is extremely simple—compared to pour-over coffee, it's practically child's play.

What is Cold Brew Coffee?

Let's dive into cold brew coffee with FrontStreet Coffee!

As the name suggests, cold brew coffee refers to coffee extracted at low temperatures. It's often confused with iced coffee, which typically refers to coffee extracted at high temperatures and then cooled with ice cubes when served. Therefore, the biggest difference between cold brew coffee and regular iced coffee lies in the extraction temperature. So what exactly is cold brew coffee? Cold brew coffee, known in English as Cold Brew Coffee, is made by grinding coffee beans into coffee powder and steeping them in cold water for at least 12 hours, then extracting and filtering through professional equipment. For a richer body, the time can also be extended to 24-48 hours.

FrontStreet Coffee believes that although cold brew coffee takes a long time to prepare, it doesn't require any special brewing techniques. With just a bottle, a bag of beans, and overnight steeping, you can wake up to a full-bodied, rich iced coffee. This is also why many people love cold brew coffee. The principle of making cold brew coffee is very simple—just master the coffee-to-water ratio, and through long steeping (over 12 hours), you can get a refreshing cold coffee. Grind and brew at home the night before, refrigerate overnight, and you can enjoy ice-cold coffee the next morning when you wake up. That feeling is quite refreshing, isn't it?

The extraction method differs between cold brew and pour-over coffee. Cold brew, extracted at low temperatures, contains much fewer bitter substances, and the preparation method is simple. FrontStreet Coffee believes anyone can make a delicious cold brew coffee, of course, provided they master the coffee-to-water ratio!

FrontStreet Coffee's Cold Brew Coffee Method

As FrontStreet Coffee just mentioned, making cold brew coffee is extremely simple, especially compared to pour-over, it's even more straightforward. As long as you use the right parameters, you can easily make delicious iced coffee. So how should we choose parameters like grind size and coffee-to-water ratio for making cold brew coffee?

FrontStreet Coffee typically recommends a coffee-to-water ratio of 1:12 for cold brew, based on 50 grams of coffee powder. The cold brew coffee made with this ratio has just the right concentration and can be tasted directly without dilution. Some friends prefer to add milk/soda water or use it to make specialty coffee drinks. In this case, you need to increase the coffee concentration. FrontStreet Coffee recommends a ratio of 1:10 for making cold brew coffee intended for specialty drinks.

Cold Brew Coffee Grind Size

The grind size of coffee is related to brewing. Since cold brew coffee uses ice water for extraction, the extraction efficiency is extremely low—in other words, you don't have to worry about over-extraction at all. FrontStreet Coffee chooses a slightly finer grind size for cold brew than for pour-over, with 85% pass-through through a #20 standard sieve as a reference, with as few fine particles as possible. However, FrontStreet Coffee reminds everyone to note that although low-temperature extraction can reduce the appearance of bitter substances, it's not 100% effective. If the grind is too fine, the sweet and sour substances in the coffee powder will be extracted quickly, followed by the release of rich body substances. An appropriate amount of these substances can enhance the coffee's body, but if steeped for too long, woody flavors will begin to appear, reducing the overall cleanliness of the coffee.

Coffee-to-Water Ratio

Some friends might ask: So how much water is most appropriate for steeping? FrontStreet Coffee's standard is a powder-to-water-to-ice ratio of 1:8:4, meaning the actual powder-to-water ratio is 1:12. Ice is added to ensure the water temperature is sufficiently low, maintaining extraction efficiency at a stable level.

Temperature

FrontStreet Coffee has mentioned that for pour-over coffee, water temperature is related to the degree of roast, while cold brew coffee temperature doesn't need strict control—it just needs to be placed in a refrigerator for low-temperature extraction. When extracting at low temperatures, the extraction time needs to be 24 hours. So can cold brew coffee be extracted at room temperature? Cold brew coffee can certainly be extracted at room temperature, but this means a shorter extraction time. FrontStreet Coffee recommends shortening the extraction time to 8 to 12 hours for room temperature extraction.

FrontStreet Coffee's cold brew method is based on 50 grams of coffee powder. After grinding the coffee beans, place them in a clean, oil-free sealed container. Add 400 milliliters of room temperature water and 200 grams of hard ice cubes (totaling 600 grams of ice-water mixture). Seal the container and shake gently to ensure the coffee powder is fully in contact with the ice water, then place it in the refrigerator for 12-24 hours. After extraction, use filter paper or a fine mesh sieve to filter out the coffee grounds, then store the coffee liquid in a clean sealed bottle and refrigerate for about 4 hours before drinking.

How Long Can Cold Brew Coffee Be Stored After Filtration?

FrontStreet Coffee has discussed how to drink pour-over coffee—different temperatures offer different flavors, but it shouldn't be left for too long. For example, if left for a day, it should still be consumed as soon as possible. Cold brew coffee, however, is different. Theoretically, the longer cold brew coffee sits, the more intense its fermented flavor becomes. But excessive fermentation can cause the coffee to lose its original flavor. For friends who don't like too strong of a fermented taste, FrontStreet Coffee doesn't recommend trying this lightly. The best time to enjoy cold brew coffee is 2-3 days after filtering the grounds, and it's recommended not to store it for more than 7 days.

Low temperature and long extraction time are the two main characteristics of cold brew coffee, as well as the two main differences between cold brew and hot brew coffee. Hot brew coffee extracts coffee powder with hot water at temperatures between 88-91°C, generally not exceeding 5 minutes. The fastest espresso takes only 18-23 seconds, while cold brew coffee takes far longer than hot brew coffee. Regarding the issue of cold brew coffee's longer extraction time, FrontStreet Coffee puts it poetically: "You're drinking not just a cup of coffee, but a long period of waiting."

Characteristics of Cold Brew Coffee

In terms of flavor, high temperatures cause tannic acid in coffee to decompose into quinic acid, creating acidity and bitterness. Studies have shown that acidic substances in cold brew coffee are 67% lower than in hot brew methods. Therefore, compared to hot brew coffee and hot brew coffee with ice added later, cold brew coffee has lower acidity and bitterness, making it widely popular. For friends who don't like acidic coffee, cold brew coffee is perfect!

Additionally, FrontStreet Coffee has found that the low-temperature conditions and prolonged contact with coffee powder mean that only small molecular flavor compounds are extracted, such as floral and fruit aromas, while larger molecular flavor compounds like smoky and roasted flavors are difficult to extract. This is why cold brew coffee doesn't have a striking aroma when smelled, but tastes smoother, richer, with distinct layers and obvious sweet aftertaste, without any greasy feeling.

Of course, all of this is premised on ensuring the freshness of the coffee beans. FrontStreet Coffee deeply understands that coffee bean freshness has a significant impact on flavor. FrontStreet Coffee's roasting philosophy is "Freshly Roasted Quality Coffee," ensuring that every customer who places an order receives the freshest coffee when it arrives. Therefore, FrontStreet Coffee ships coffee beans roasted within 5 days. The coffee's resting period is about 4-7 days, so when customers receive it, it's at its peak flavor.

FrontStreet Coffee believes that any coffee preparation method requires continuous practice to better bring out all the flavors of the coffee. FrontStreet Coffee has dozens of different single-origin coffees to allow everyone to better experience different coffee flavors. Friends can also come to FrontStreet Coffee to discuss coffee with our baristas!

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