Complete Guide to Making Cold Brew Coffee at Home
Cold brew coffee just keeps getting more popular. Perhaps you’ve tried it at your local coffee shop, but did you know that it is easy and less expensive to make it yourself at home?
I’ve been making cold brew at home almost every day for over 8 years now. In this guide I will show you everything you need to know to brew your own delicious cold brew coffee.
Key Points
What is cold brew coffee?
Cold brew coffee is coffee brewed without hot water. The temperature of the water can be room temperature or cooler, but never hot.
How is cold brew coffee made?
There are two main methods for making cold brew: immersion or drip.
Both have their pros and cons, but one thing they have in common is they both take time. In this era of coffee pods, where you can have a hot cup of coffee in minutes, this is like the slow food of the coffee world.
The immersion method involves soaking coffee grounds in water for an extended period of time, usually 8-24 hours, and then straining out the grounds.
The advantages of the immersion technique are it is simple and uses equipment you probably already own. You can start today.
The disadvantage is it takes longer to brew coffee this way.
Cold drip coffee is made by letting cool water drip through a bed of coffee grounds. This usually takes a couple of hours.
The advantages are that it makes a smoother brew (in my opinion), and it takes less time.
The disadvantage is you do need a special brewer to do this.
| Immersion | Drip | |
| Brew Time | 8- 24 hours | 2-3 hours (depends on volume) |
| Pros | Simple No special equipment | Faster Rich, full bodied result |
| Cons | Takes longer | Requires special brewer |
How to Make Cold Brew By Immersion
Immersion is a popular and simple technique for making cold brew at home because it doesn’t really require any special equipment. Most of what you need you probably already own .
With the immersion technique you simply soak coffee grounds in water for several hours and then strain out the grounds.
With the immersion technique, you can adjust the coffee to water ratio and make a cold brew concentrate or something that’s closer to ready to drink.
The key to any cold brew coffee is to not skimp on the coffee grounds. If I have a mantra it is:
You can always add water to coffee that is too strong, but you can’t rescue cold brew that is too weak.
Basic Technique:
- Measure out coffee grounds into a container. I prefer glass, such as a mason jar.
- Add water and swirl a bit to wet the grounds
- Let steep for 8 to 24 hours on a counter top or in the fridge (I recommend the fridge, more on that below)
- Pour the coffee and grounds through a coffee filter or cheesecloth and recycle, compost, or discard your coffee grounds
- Enjoy your homemade cold brew
That’s the basic how-to, but let’s explore a few details for brewing your perfect cup.
What is the Best Ratio of Coffee to Water to Use?
The first question most people have when they start to brew their own cold brew coffee is how much coffee should they use?
The perfect ratio is the subject of much debate in coffee forums. Part of the answer will depend if your aim is to make a concentrate that you can later dilute or a ready to drink cup.
For a concentrate, use one part coffee to 2 parts water . So for example, 1 cup of coffee grounds and 2 cups of water.
Now for those of you used to brewing hot coffee, that’s a heck of a lot of coffee grounds, but this ratio yields a concentrate that can be diluted approximately 50% with water. So in effect this produces 3-4 cups of finished cold brew depending on how strong you like it.
If you like your coffee strong, I suggest making a concentrate like this since it gives you the freedom to dilute your coffee to taste.
Try being stingy with the coffee and you may end up with a weak, insipid brew.
If you prefer to try and brew something closer to ready to drink, try a ratio of one part coffee to 4 parts water.
My go-to is roughly 1 part coffee to 3 parts water. I say roughly because I just eyeball it. I add some coffee to my jar. And then I add enough water to make it look triple in volume. Is this a true 1:3 ratio? No, but it is easy and reliable.
Check out this handy graphic to see what I mean.
With this technique there is no measuring and it always turns out strong enough to dilute with a splash of water and still be nice and strong.
What kind of coffee should I use when making cold brew?
This is largely a matter of personal preference. Light roasts tend to have a fruitier flavor while dark roasts are a bit smokier in flavor. I tend to choose medium roasts for the best of both worlds.
Arabica coffee beans from Central or South America are used by many of the commercial coffee companies. A runner up is Ethiopian coffee.
Read more about the best beans for cold brew coffee.
Experiment with a few different varieties and see which you prefer. There is no right answer here as taste is really a matter of personal preference.
Use Medium to Coarsely Ground Coffee
The size of grinds can make a difference in your final result. Fine ground coffee such as is used for espresso is not recommended because it’s easier to get an over extracted, bitter result.
A finer ground coffee has more surface area in contact with water, maximizing extraction but possibly to the point of over-extracting. Over-extracted coffee can taste more bitter. Not what we want.
Because we are dealing with long extraction times, using a medium to coarsely ground coffee produces a better result by decreasing the surface area of the grounds.
Many supermarket coffees come in fine or medium grind, so does this mean you need to grind your own beans?
Well generally the freshest most flavorful coffee will always come from freshly ground beans. In order to get a nice coarse ground, I recommend using a burr grinder that lets you select your grind size.
But, if you don’t want to grind your own you don’t have to. I have successfully used pre-ground coffee many times and it works just fine.
With the popularity of cold brew several roasters are now selling coarsely ground coffee marketed at cold brew drinkers.
What is the best water to use for cold brew coffee?
Cold brew coffee is made from coffee beans and water. So, we want to make sure both are just right in order for our coffee to taste great.
I recommend filtered water. Some options include:
- Filtered water from your built in fridge dispenser
- Adding a filter to your faucet
- Bottled water
- Using a filter pitcher such as a Brita
How long does it take to make cold brew coffee?
Hot water does a great job of extracting coffee flavors from the beans. Cold or even room temperature water isn’t as efficient.
We compensate for this by soaking the coffee grounds for longer. This is why cold brew can’t be rushed.
Generally it takes between 8 to 24 hours to make a good cup of cold brew coffee. I don’t recommend longer than 24 hours as it can over-extract the coffee and make it taste bitter.
Researchers have found a lot of the coffee compounds have been extracted in as little as two hours, but I find the flavor improves if you let it steep longer.
Many commercial cold brew manufacturers brew for between 16 to 20 hours. I often mix up my cold brew in the evening and strain it the next morning about 7-8 hours later and it works just fine.
Bottom line: Aim for 14-20 hours as that seems to be the sweet spot, but don’t worry if you brew a little longer or shorter than that. It will be fine.
Should You Brew in the Fridge or on the Counter Top?
You may find several recipes out there advocating steeping cold brew at room temperature. This works but personally I have stopped doing this.
You see, water has this nasty habit of growing things when left to sit. On top of this, coffee is considered a low acid food so it doesn’t inhibit microbial growth very well.
If you brew on the counter top, you will want to make sure that all of your brewing equipment is very clean. I recommend washing your brewing equipment in the dishwasher so the very hot water can sanitize it.
I have started brewing my coffee in the fridge. Keeping the brew in the fridge slows down microbial growth. Of course using clean brewing equipment is still best practice even in the fridge.
When brewing at colder temperatures you may want to brew a little longer to ensure adequate extraction of the coffee .
Some folks blend this approach, letting the coffee sit for up to two hours at room temperature and then refrigerating it. This should be fine from a safety standpoint. I can be forgetful so I just put mine straight in the fridge.
Read more: 4 Factors for Great Cold Brew Coffee
How to filter your cold brew coffee
Once your coffee is done steeping it’s time to filter out the grounds.
There are two main options for this:
- a coffee filter in a pour over coffee maker or mesh strainer
- a coffee bag or sock
For me the coffee filter method is the easiest and cleanest. I use white cone filters as I find the unbleached ones have a slight bit of paper taste to them.
I use a pour over coffee maker to support the filter and I can pour in some coffee and go do something else while it strains.
When using a coffee sock or bag you can actually steep your coffee right in the bag. Then when you are ready to filter you just remove the bag and maybe give it a little squeeze to get all the coffee out and you are done. Kind of.
The nice thing about coffee bags is they are eco-friendly and reusable, the not so nice thing is that they can be a bit of a pain to clean when coffee grinds get stuck in the seams (and believe me they will!)
It’s important to get the bag thoroughly clean so that the flavor and safety of your next batch isn’t affected by old coffee grounds.
Using a French Press for Immersion and Filtration
If you have a French press coffee maker this can be a great way to make cold brew by immersion. You can steep the coffee grounds directly in the French press and when you’re ready to strain push the plunger down.
I like to let the grounds settle just a little bit before pouring as I find a French press does allow some sediment into my finished coffee. Of course the coarser the grind the less of a problem this is.
You can read more about making cold brew in a French press here.
Using Cold Brew Coffee Makers
There are several cold brew coffee makers on the market. These range from glorified mason jar systems to pitchers with stainless steel filters to machines that swirl or pump the coffee to accelerate extraction.
All of the above work on the principle of immersion. You don’t need a special cold brew maker to make cold brew coffee by immersion, but they can be nice.
For example, if you don’t have a way to filter your coffee, you could get a pitcher with filter basket built in.
If you don’t have any glass containers you could buy a mason jar coffee maker rather than investing in a set of mason jars (which often come in packs of 6 or 12 jars and have wonky two piece lids meant for canning).
If you want to try a rapid cold brewer, you can do that as well. I have tried a couple of these and wasn’t terribly impressed.
Presto Dorothy Rapid Cold Brew Maker Review
Making Cold Brew with the Drip Method
Cold drip coffee is the other main method for extracting coffee without heat.
This method does require special equipment, however there are a few products on the market that are more affordable than the fancy glass towers you may see at a high end coffee shop.
One advantage of cold drip coffee is you can be drinking coffee in just a few hours. Not exactly instant cold brew, but the next best thing!
Equipment Needed
You may also see the cold drip method referred to as Kyoto or Dutch style coffee. Traditional cold drip towers are elaborate glass and wood affairs that can cost in the hundreds of dollars.
More practical for the home users are devices like the Dripo (my favorite but sadly seems discontinued) and the Bruer.
Basic Cold Drip Technique
The exact technique for cold drip coffee will vary slightly depending on the cold drip maker that you are using.
In general, coffee grounds are placed in the device with a small piece of filter paper over them.
Cold water (often with a little ice) is placed in a container above the grounds and the water falls through drip by drip.
The function of the filter paper is to spread out the drops of water across all of the grounds so that the water doesn’t just drip through the center of the coffee.
No straining is required since the coffee is in a filter basket already. Just grab your coffee from the bottom receptacle when it’s done.
For me, cold drip coffee has a superior taste when compared to immersion coffee. It has a richness that I don’t get with immersion brews.
As a note, I use the maximum recommended amount of coffee that my drip brewer recommends to get a full bodied result. Did I mention never skimp on the amount of coffee?
FAQ
How long can I store my brewed coffee for?
Cold brewed coffee does not contain some of the coffee oils that hot brewed coffee does so it doesn’t oxidize or grow rancid as quickly.
Note: oxidation and rancidity refer to oils developing an off taste and is not the same as the microbial growth discussed earlier in this post.
Personally, I would keep cold brew in the fridge for up to a week. In my house, a batch rarely lasts that long.
The best taste is usually in the first 2-3 days, then I start to notice a deterioration in flavor.
Can cold brew coffee be frozen?
Yes! In fact, if you have a little leftover coffee go ahead and make some coffee ice cubes out of them.
You can use these in your coffee and it won’t get diluted when the ice melts.
After making your cubes, store them in an airtight container for up to six months for best taste.
Can I heat cold brewed coffee?
Yes, in fact William Ukers, in his exhaustive book All About Coffee (1922) describes a British practice of brewing at room temperature overnight, and then very gently heating the strained coffee in the morning.
My first introduction to cold brew in the 1990’s was when an acquaintance described a similar practice of brewing a cold brew concentrate and then diluting it with boiling water to make a hot cup of coffee.
Either way, it can be done.
How does cold brew differ from iced coffee?
Cold brew is made from cold or room temperature water.
Iced coffee is brewed hot and then cooled. This can be done by refrigerating the hot brewed coffee, or by immediately pouring it over ice (e.g. iced Americano) or using the Japanese Pour Over Ice Method.
The main difference will be one of flavors as hot water extracts certain flavor components from coffee that cold brewing doesn’t. It is these same flavor components that give hot brewed coffee its more bitter notes.
Can I make cold brew coffee with whole beans?
I’ll be honest, I have not tried this but you would definitely be limiting the surface area of the coffee in contact with the water.
I have used coarsely chopped coffee beans to make a coffee infused milk and/or cream for some of my recipes and it worked quite nicely.
If you don’t have a coffee grinder, I would at least chop them up a bit before trying this.
Here are a couple recipes that use coffee brewed in milk or cream:
Cold Brew Crème Brulee
Cold Brew Ice Cream
So if I like my coffee with milk, can I just brew coffee directly in milk?
You can, but it won’t be the same. Instead of an iced latte type of drink you will end up with coffee flavored milk.
This is great for recipes (see question above) but may not be quite what you had in mind for drinking.
You can read how to make cold brew in milk here and give it a try. You won’t know if you like it until you do.
Whether you immerse or drip your cold coffee, I think you will agree that making cold brew coffee at home can save you a lot of money over buying it at the coffee stand or in a bottle.
