What is Cold Brew Coffee? How to Make Cold Brew Iced Coffee? How Long Does Cold Brew Take? Cold Water or Hot Water?

Cold brew coffee is one of the essential beverages we can enjoy during hot summer days. Standing in front of FrontStreet Coffee's blackboard, looking at the dazzling array of coffee varieties, all knowledge about growing regions is suddenly forgotten, leaving one unsure where to start. This time, let FrontStreet Coffee introduce you to the world of cold brew coffee.

What is Cold Brew Coffee?

Cold brew coffee is completely different from regular hot coffee brewing methods. Judging from the literal meaning, cold brew coffee uses low-temperature water to extract coffee. However, perhaps because iced pour-over coffee or iced Americano are served with ice + coffee, FrontStreet Coffee has encountered many people who mistakenly consider iced pour-over coffee as cold brew coffee.

To clearly distinguish what cold brew coffee actually is, you only need to look at the water temperature used during the extraction process. Cold brew coffee typically uses room temperature or even low-temperature water close to 0°C for extraction. This means that whether it's iced Americano or iced pour-over coffee, even if served at a low temperature, since hot water is used to contact the coffee grounds during extraction, neither can be considered a type of cold brew coffee.

Cold brew coffee can be roughly divided into two types based on different production methods. One is cold brew coffee where coffee grounds are completely soaked in low-temperature water for extended extraction time; the other is ice-drip coffee where ice water drips drop by drop onto the coffee grounds for extraction.

At FrontStreet Coffee's stores, due to equipment limitations, FrontStreet Coffee's cold brew coffee offerings only include ice-drip coffee for selection.

The key point of cold brew coffee is: very low temperature. First, one concept to understand is that coffee beans contain 30% soluble substances, but coffee making is simply a process of extracting some of the better-flavored substances from the coffee. The higher the water temperature used, the faster various soluble substances in the coffee are released: among them, acidic substances move fastest; followed by sweet substances; while bitter substances move slowest. The increase in temperature is also accompanied by an increase in the total amount of these flavor substances.

Conversely, if the water temperature is very low, to extract a certain amount of flavor substances, the required extraction time becomes longer. This is why, if you want to taste ice-drip coffee made from specific coffee beans at FrontStreet Coffee's store, you need to place an order two days in advance.

What Coffee Beans Are Suitable for Making Cold Brew Coffee?

During the production process of cold brew coffee, the water temperature used is relatively low, and after coffee grounds come into contact with water, the release rate of flavor substances inside the coffee beans significantly slows down, which also reduces the extraction amount of some larger molecular weight bitter substances, thus highlighting the coffee's sweet and sour flavors.

As such, FrontStreet Coffee suggests using some lighter roasted coffee beans with good acidity such as Kenya, or coffee beans with prominent and unique flavors such as Honduras Sherry.

FrontStreet Coffee's Process of Using Honduras Sherry Coffee Beans to Make Ice-Drip Coffee

Next, FrontStreet Coffee will use Honduras Sherry coffee beans as an example to explain the cold brew coffee making process. First, let FrontStreet Coffee introduce this bean to everyone.

Honduras Sherry coffee beans use a processing method of refined washed + Sherry whiskey barrel fermentation. Cleaned parchment beans are placed in Sherry whiskey barrels for low-temperature fermentation for 30 to 40 days, allowing the aromatic substances from the barrels to better penetrate into the raw coffee beans. Finally, they are spread evenly to dry in a cool place to avoid the aromatic substances decomposing into unpleasant wine acidity due to excessive temperature from direct sunlight.

In the world of whiskey, malt undergoes germination, drying, grinding, saccharification, fermentation, and finally the distilled liquid is put into barrels for long-term aging. Among them, 75% of whiskey flavor comes from the aging wooden barrels, and using different materials or barrels soaked in different liquids for aging will result in different flavors. Among various types of whiskey, sherry cask whiskey has captured a large number of whiskey connoisseurs and whiskey novices with its rich sweet flavor. FrontStreet Coffee's Honduras Sherry coffee beans, due to being fermented in Sherry whiskey barrels at low temperature, inherit some of the sweet sensation of Sherry whiskey to a certain extent.

When FrontStreet Coffee developed the roasting curve, to preserve the gentle acidity of Central American beans, Honduras Sherry coffee beans were roasted to a medium degree.

FrontStreet Coffee conducted cupping on the roasted Honduras Sherry and tasted rich vanilla and cream flavors, gentle berry acidity, and after the berry acidity dissipated, a distinct oak barrel aroma emerged.

Coffee amount: 60 grams

Coffee-to-water ratio: 1:10

Water temperature: 0°C - 4°C

Time: 6-8 hours

Grind size: 85% pass rate through China No. 20 standard sieve

Use 60 grams of coffee grounds to extract 600 milliliters of coffee liquid, with a cold brew coffee-to-water ratio of 1:10. In terms of grind size selection, because the water temperature contacting the grounds is lower compared to regular pour-over coffee, a slightly finer setting than pour-over coffee is chosen. Judging by the No. 20 sieve, the pass rate will be around 85%. The ratio of ice to water is approximately 1:1, and the throttle valve controls the flow rate at 7 drops per 10 seconds. A moistened filter paper is placed on top of the coffee bed for more even extraction. The entire extraction process takes approximately 6-8 hours. After extraction is complete, the coffee liquid is bottled and refrigerated for 12 hours before drinking.

After a night of fermentation, the ice-drip coffee made with Sherry coffee beans has distinct berry acidity, along with the rich sweetness of chocolate, nuts, and dried fruits found in Sherry whiskey, with a heavy mouthfeel and fermented character.

How Long Can Cold Brew Coffee Be Stored?

Since cold brew coffee takes a long time to make, some people prefer to make it in batches and store it for later use. The question "how long can cold brew coffee be stored" has troubled many people.

FrontStreet Coffee suggests that freshly made cold brew coffee should be stored in sealable containers and kept refrigerated.

After cold brew coffee is extracted and sealed for storage, the coffee liquid begins to ferment. As time extends, the fermented flavor becomes increasingly rich, eventually producing the taste of spoilage. FrontStreet Coffee has kept records showing that on the fifth day of refrigeration after cold brew coffee is made, the coffee flavor diminishes, replaced by a rich fermented sensation. For safety reasons, FrontStreet Coffee suggests that cold brew coffee should be consumed within one week after extraction is complete.

For professional coffee knowledge exchange and more coffee bean information, please follow Coffee Workshop (WeChat public 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