How to Make Ice Drip Coffee at Home Office How Long Can Cold Brewed Coffee Be Stored at Refrigerator or Room Temperature

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The Rising Popularity of Cold Drip Coffee

As the weather gradually becomes hotter, cold drip coffee at FrontStreet Coffee's stores has once again fallen into a state of short supply. Through interviews with FrontStreet Coffee, we found that many people choose cold drip coffee among various iced coffees not only because its taste and flavor differ from other conventional iced coffees, but also partly because they cannot make it at home.

Cold drip coffee is a type of cold brew coffee made by dripping ice water over an extended period. Its preparation typically requires a professional device called a cold drip tower. Because the extraction efficiency of ice water is extremely low, we need to use the flow restrictor valve of the cold drip tower to release ice water in droplet form, thereby extending the extraction time and allowing the coffee to achieve complete extraction.

A Simple Alternative Method

However, for individual coffee enthusiasts, a cold drip tower is not an essential item. This is both because its practicality is not that significant, and because of its considerable price and cumbersome operation steps. This deters many people, who would rather go out to buy a cup of cold drip coffee than spend money on a tower to make it at home.

But in reality, cold drip coffee doesn't necessarily require a dedicated cold drip tower to be made. There happens to be an alternative method that not only requires very simple equipment for making cold drip coffee, but is also extremely easy to operate, not complicated at all! That's right! It's a method that FrontStreet Coffee has been sharing and that has been very popular online—directly using ice cubes and a drip cone to replace the function of a cold drip tower to make cold drip coffee.

The specific operation is very simple. We just need to find a drip cone to hold the coffee grounds, then directly place ice cubes above the coffee grounds, and a simple "home version" cold drip tower is complete. As time passes, the ice cubes on the coffee grounds will gradually melt into water and begin extracting the coffee. As long as the making environment is not very hot, the melting speed of the ice cubes is not as fast as everyone imagines. Therefore, this method can also allow the coffee to achieve relatively complete extraction, producing a cup of rich-tasting cold drip coffee.

Important Considerations

Although it's very simple, there are quite a few issues that need attention. One wrong step can prevent the coffee from achieving complete extraction, resulting in a less rich flavor. Therefore, in sharing the making process, FrontStreet Coffee will list these problems, and everyone should avoid these pitfalls when making it.

"Home Version" Cold Drip Coffee

First, FrontStreet Coffee will introduce the equipment needed to make "home version" cold drip coffee: any container to collect the coffee liquid, 1-2 coffee drip cones, and 2 filter papers that fit the drip cones. For materials, you only need to prepare coffee grounds and ice cubes! That's right, these are just the things we usually use when making pour-over coffee, it's that simple.

Choosing the Right Beans and Grind Size

For this demonstration, FrontStreet Coffee used Costa Rican Strawberry Sugar beans, but you can choose your favorite beans according to your preferences. In terms of parameters, there's one point we need to pay special attention to, which is the grind size.

Generally, the powder chamber design of a cold drip tower is a narrow, long cylinder. This design can increase the thickness of the coffee bed, allowing hot water to pass through more coffee grounds to extract more substances. In contrast, drip cones are designed with a narrow bottom and wide top to achieve more even extraction. When the same amount of coffee powder is poured into a drip cone, the coffee bed formed is not as thick as that formed in a cold drip tower's powder chamber. This means that with the same amount of water, the reduction in path length will result in fewer extracted substances.

Therefore, if we want the coffee grounds to achieve the same extraction rate, it's best to adjust the grind one level finer than usual. By grinding finer, the gaps between coffee particles are reduced, increasing the area through which water needs to flow, allowing extraction to be complete. The parameters are as follows:

Coffee amount: 25g
Ice-to-coffee ratio: 1:10
Grind level: Ek43's 8.5 setting, 90% pass-through rate with a #20 sieve (slightly finer than fine sugar, two levels finer than for hot pour-over)

The Making Process

When the materials are ready, we can start making cold drip coffee. First, we wet the filter paper, pour in the coffee grounds, then use room temperature water equal to the amount of coffee to "bloom" the coffee grounds.

The purpose of this blooming step is not to release gases, but to wet the coffee grounds so that the subsequently dripping ice water can extract coffee grounds outside the immediate area through capillary action. It's worth noting that in this step, we should try to keep the pouring height as low as possible and reduce the amount of water poured to prevent the water from creating holes in the coffee bed, which could lead to under-extraction.

After pouring is complete, some water will pass through the coffee layer directly into the lower container. We can pour out all this water because, due to its low temperature, it doesn't carry much coffee substance, and keeping it would only dilute the coffee extracted later. Next, we cut two filter papers approximately the same size as the coffee bed surface (circular filter paper is fine if there's not much coffee) and place them flat on the coffee bed, then wet them. Because ice water drips in the form of droplets, to enable them to extract the coffee grounds more evenly, we need to use filter paper to disperse them. This step cannot be omitted.

When the filter paper is laid out, we can place ice cubes directly on it. Since the space on the drip cone isn't large enough to accommodate all the ice cubes needed, we can add the ice cubes in batches.

If you have two drip cones, you can directly choose to use a drip cone to hold the ice cubes (as shown in the right side of the image below). This way, you can add all the ice cubes at once without constantly monitoring the melting progress of the ice cubes to decide whether to add more. It's important to note that you must place filter paper in the drip cone before adding ice, otherwise, when the ice cubes melt to a certain size, they will pass directly through the filter holes of the drip cone, delivering a "heavy blow" to your even coffee bed.

Finally, we just need to wait for all the ice cubes to melt completely, then remove the drip cone, and the coffee extraction is complete!

The Final Step: Cold Fermentation

But at this point, the making of cold drip coffee is not yet finished! The cold drip coffee is not yet formed; it needs to develop its flavor and alcoholic aroma through long-term refrigeration and fermentation. Therefore, at this point, we need to use plastic wrap or prepare an additional sealed bottle to seal the cold drip coffee, then place it in the refrigerator for cold storage.

After 8 hours, the cold drip coffee is officially complete. At this point, you can choose to enjoy it with ice, or extend the refrigeration and fermentation time to make its alcoholic aroma even richer.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473