The rules of brewing coffee remain the same whether you’re using hot or cold water. If you over-extract, the bitterness will make the beverage undrinkable. Conversely, if you under extract, you’ll be drinking lightly flavored water rather than coffee. Coffee machines have the extraction sweet spot programmed into them, so you don’t need to worry about such details.
However, with a cold brew, you’re often in charge of determining how you extract the coffee. Rather than gamble and risk messing up your beverage, you can learn how long to steep cold brew to get the best results below.
By definition, a cold brew is a drink brewed using either cold or room temperature water. Unfortunately, cold water doesn’t extract coffee flavor or caffeine as fast as hot water, which is why it needs more time to interact with the grinds. This is also why steeping is necessary.
Ultimately, if you don’t steep your grinds for long enough, there isn’t going to be sufficient interaction between the water and coffee for flavor extraction. Consequently, you’ll end up with a diluted, watery beverage.
Conversely, it’s possible to over-extract by leaving the water to interact with the coffee for too long. The resulting beverage would be bitter and have a dusty aftertaste. Consequently, there is a sweet spot that gives you the best beverage outcome. However, this sweet spot does vary depending on several factors, as you will learn below.
Notably, the sweet spot is not a specific time but rather a range. This is because several factors, e.g., the brewing method, the coffee type, grind size and whether you’ll refrigerate the beverage or not, affect the interaction between the coffee and the water. We discuss the effects of these variables on your coffee and the steeping time below.
Notably, the only requirements for a cold brew are for cold water and coffee grinds in the proper ratio to interact long enough to extract flavor. How you achieve this interaction will depend on the cold brew coffee maker you have, which can also affect the brewing method.
Notably, according to most reviews, even the Aeropress coffee maker can be modified to make a cold brew, and it’s lightweight and portable enough to take backpacking and camping. That said, the most common options are the cold brew drip system method and the immersion method. One is often faster than the other, although ultimately, the flavor profile is slightly different.
The coffee type also matters. After all, there is a difference between cold brew and cold brew concentrate. The latter should be diluted before you put it in your mouth. The former is ready to drink as soon as it’s done brewing. Cold-brew concentrate uses less water and may need to be diluted later with either water or milk.
There’s also nitro cold brew coffee which is made by adding nitrogen to a cold brew. According to WBUR Trusted Source Nitro Cold Brew: The Science Behind Coffee's Biggest Trend Nitrogen bubbles give cold brew a silky smooth texture and enhance its flavor. www.wbur.org , not only does the nitrogen enhance the coffee flavor, but it also gives it a smoother texture. That said, the gas needs to be bubbled through the beverage, and you need a nitro brew coffee maker for that.
The next variable is the grind size. Typically, finer grinds are easier to extract since they expose more of the surface area of the coffee to the water. This is also why fine grinds are used for espresso. Ultimately this makes finer grinds unsuitable for a cold brew as there is a high risk of over-extraction even if you leave the beverage brewing for just a few hours.
Consequently, you should use coarse ground coffee beans for a cold brew if you want the right level of extraction. Also, considering the cold brew setup, there’s a chance that finer grinds will find their way into the final beverage and spoil it.
Brewing coffee is technically a chemical process with reactions between the grinds and water. Also, according to Lumen Learning, Trusted Source Factors Affecting Reaction Rates | Chemistry Describe the effects of chemical nature, physical state, temperature, concentration, and catalysis on reaction rates courses.lumenlearning.com chemical reactions happen faster at higher temperatures, and this can only mean that refrigeration will lengthen the brewing time.
You can let the coffee brew in the refrigerator since most people prefer the beverage chilled. However, it doesn’t make a difference to the flavor whether you refrigerate the beverage before or after it’s done brewing.
Again, how long you let cold brews steep will depend on the brewing method you choose. Below are your most viable options.
The standard method is where you brew the coffee with room temperature water. You’ll only need a glass mixing container and something to filter out the coffee.
Notably, the coffee to water mixing ratio differs depending on the results you want. If you’re drinking the coffee without diluting, a 1:5 or 1:4 ratio in favor of the water is ideal.
For cold brew concentrate, the ratio should be 1:1 or 1:2 in favor of the water, depending on how strong you want the beverage to be. After that, you leave the mason jar and coffee-water mix on the counter for 12 hours before filtering out the grinds and serving.
The long method is more or less a variation of the standard method. Again you’ll need something like a mason jar or somewhere to store the coffee and water mixture while it brews.
Many reviewers recommend the County Line Kitchen cold brew coffee maker because despite looking a lot like a regular mason jar, it comes with a stainless steel filter for your grinds. Additionally, there’s the leak-proof lid dispenser for when you’re done brewing and need to serve the beverage.
You’ll still mix the coffee and water in the same ratios. However, this time you’ll leave the mixture in the fridge for 18 hours before filtering out the grinds and serving.
The drip/quick system takes roughly 8-12 hours to complete. However, for this option, you’ll need a slightly advanced drip system with a faucet that you can control. That way, you can keep the water dripping into the coffee for as long as possible.
You’ll use the same course ground coffee you use for other cold brew methods. A paper filter on top of your grinds in the filter basket prevents splashing. This hack also distributes the water over the coffee more evenly.
After that, you’ll pour chilled water into the drip system and open the tap ever so slightly. You can even use ice cubes, so they melt as they drip slowly into the coffee basket and the jar below it. After 8 hours, you should have collected more than enough cold brew to drink.
Now you know how long to steep cold brew depending on whether you’re using the standard, drip system, or the long method. Remember, you don’t have to consume the beverage straight away. Unlike hot coffee beverages, you can store it in the refrigerator for up to seven days with no flavor loss. As such, you can make enough for the week in advance.