Cold Brew Coffee




Introduction: Cold Brew Coffee

I've been a Barista in high end coffee for about 4 years now. One of the things you learn early on is that it is distasteful to ever ice espresso. Many go forward never questioning why this is such a bad idea, but I have an inquisitive mind and looked into it further.

It turns out that coffee is high in chlorogenic acid, which, as the coffee cools, forms quinic acid, which has a noteable and overwhelming astringent flavor. So the task is to brew coffee in a way that does not involve heat, and also reduces the apparent acidity. In the 60's the Toddy method became popular and it produces a finished product that is notably less bitter and actually puts forward a deep caramel and chocolaty flavor. Cold brew coffee is perfect for a warm day.

I decided to make my own cold brew coffee brewer.

Step 1: Materials

-6oz of a well roasted coffee
-one piece of felt (.29 cents at michaels)
-two large coffee filters
-a two-liter bottle

Step 2: Begin

Cut the bottom off of the two-liter bottle.

Step 3: Stand

Use a broad glass to act as a stand for the brewer

Step 4: Filter

Fold a piece of felt

Step 5: Filter Insertion

Roll up the felt and stuff it into the opening of the brewer.

Step 6: Weigh

Weigh out 6 ounces of a good, quality coffee. Bad coffee will only get you bad cold brew.

Step 7: Grind

Grind to the coarsest possible setting.

Step 8: Make Coffee "tea Bags"

Split the coffee into 2-6 coffee filters - it will depend on the size filter you have. If you've got large ones, you can do it in two - for small filters you may need six.

Step 9: Tie

Tie them off with thread.

Step 10: Set in Your Brewer

Set them in your brewer, fill with a little over 6 cups of good, clean water. Give the water a second to soak into the coffee - you may be able to pour more in after.

Step 11: Brew!

Brew for 12-24 hours, this batch brewed for 14 hours.

Step 12: Take Off the Cap!

Take off the cap and a slow drip should start.


So so close

Step 14: Enjoy!

End product. A super clean, crisp, cold brewed coffee. You can use this as a concentrate and dilute with a few ounces of water or drink it straight up. Tastes delicious and huuuuuuuuge caffeine content.


The double filtration is extremely important. A lot of places that do cold brew use the reusable fabric filters, but they tend to leave solids in the coffee and it gives it a certain grittiness that I can't stand. Double filtered cold brew coffee is one of my favorite coffee preparation methods.

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250 Discussions

I use a similar technique with one expection: Vodka instead of water. Then when done I do a simple syrup with hints of Vanilla and Almond and combine them. The wife and I like to have a late cup of coffee on Fridays, and this makes a perfect adult kicker/topper to a long week. :)

I have just tried making cold brew coffee. I soaked 1 part by weight ground coffee beans with 4 parts by weight of water. When I filtered them the coffee grinds appeared to have soaked in lots of water, and at the bottom I only collected about 1/3 of the volume of the amount of water I originally used, despite leaving the filter set up for several hours. Is that what everyone else finds too, or am I doing something wrong? Many thanks!

7 replies

I make mine with 1 ounce ground to 2.5 ounce H2O, this ratio needs to be 4 H2O to 1 cold brew for like a coffee drink, I have never tried making a less stronger cold brew as I like mine very strong and since I control the brewing, roasting and grinding process it works great for me and my wife uses the 4 to 1 for her Americano's

Also, try and filter twice. I found that if I went right for the paper filter then it took forever since the grounds were clogging it up. So now I strain once from the jar with the coffee and grounds through a wire mesh strainer. Then I rinse out the jar that was brewing the coffee. Then I put a paper filter in my wire mesh strainer and pour the coffee back into the original jar. You do lose a bit but that is fine since it is concentrated. Just add additional water. What I did was I had a 1 quart mason jar that i filled with 3 cups of water and 3/4 cup of coffee. Then after straining it, it was just sitting at about 3/4 full so I topped it up with filtered water and put it in the fridge. When I drink it I pour it over ice to dilute it even a bit more.

I have also read that the sooner after you grind the coffee the less water it absorbs so try again but grind the coffee just before you use it.

My guess as to the origin of that idea would be that the sooner after roasting and grinding, the more CO2 will still be present in the structure of the coffee, so this may result in less water being absorbed in the short term...and therefore lower extraction of the soluble compounds that you want in your finished beverage! So probably trying for lower absorbtion is counter-productive. In any event, brewing for the length of time we are talking here would likely give ample time for the water to soak in regardless of how fresh your ground coffee is... next batch I roast I'll give it a try right after roasting and again a few days later, see if I can detect a difference in volume or flavour, and try and remember to post back here...

Only getting a third back seems low. I get more than this! However I don't let it drip but instead filter it twice - once in a French Press (a plunger, cafetiere, Bodum, whatever), then again in an Aeropress.

Only getting a third back seems low. I get more than this! However I don't let it drip but instead filter it twice - once in a French Press (a plunger, cafetiere, Bodum, whatever), then again in an Aeropress.

Only getting a third back seems low. I get more than this! However I don't let it drip but instead filter it twice - once in a French Press (a plunger, cafetiere, Bodum, whatever), then again in an Aeropress.

this is not a replacement for esspresso. It's to make American coffee for hot coffee and for iced coffee. It is smoother than hot brewed coffee. And you taste notes of chocolate and caramel more. But you taste coffee less. Keep your espresso maker for the purpose of a good strong pure coffee flavored shot.

1 reply

I have over the years made my Toddy coffee and have owned a espresso drive tru and I would not label this Toddy as espresso as it is not made in the way espress has been made for decades however I do not for my coffee drink ever use 200 degrees of pressured water at 130. pounds per inch to make it. For me by controlling the grind the type of my beans the ratio of grounds to water and time of soak I make a better tasting non acidic, not bitter and in my tastes more caffeine drink than the espresso machine. And I guess we should call our cold brews an American coffee drink

I really like the idea of squishing out all the goodness with a French press.

1 reply

i started using a French Press over 30 years ago when I was on the road, went to a major grocery store grabbed some of their beans, had my little grinder with me at all times, threw in the grounds filled it with water next morning I had some wonderful coffee, years later I found the Toddy Maker, when I was in the same town for a while I would use it and always traveled with a cooler, would fill it with the motel's ice to keep it cold. I might note this was in California, there was no Charbucks, oops Starbucks at that time. When I moved back to Oregon when I got off the road, I opened an Espresso drive tru used only my Toddy Maker Brew as my espresso shots, heat never touched my untill the steam milk was poured over it. By then I had figured out how to make 5 gallons at a time. Since I roast and blend my coffee I find that blending 4 to 5 different quality beans I have a coffee that is high in caffeine no acid and taste like coffee, I grind this for cold brew pretty fine not the normal course grind. I love you idea and a person can use you process very easy. Thanks for sharing

I'm too lazy! I grind a bag of coffee beans (coarse) & zip bag it into 12oz quantities-(approx 3 cups each) so I can just grab a zip bag & make more coffee "concentrate" as needed. Use more grounds for a stronger batch of concentrate if desired!

I pour the 3-ish cups of ground coffee into a gallon of "Spring Water" (88¢ at Walmart) after I remove some of the water from the gallon to make "space" for the grounds & then return some of the water to "top" the gallon off.

Let it sit on the counter for a day, shaking it occasionally & then refrigerate it overnight so it's cool when you want to use it!

I use one of those "gold" metal filters (a thrift shop find) & slowly pour the cooled coffee concentrate into another container using a large funnel Harbor Freight), like an empty water gal, pitcher or? I'm holding the filter over the funnel placed opening of the empty gallon bottle to "decant" the coffee concentrate!

I "jiggle" the metal filter if grounds start to accumulate as I pour, but if you pour the concentrate slowly enough, that might not be necessary.

My preference is a 2/3 part coffee concentrate to 1 part almond milk (or ?) with a generous splash of liquid sweetened vanilla creamer & poured over ice,...yum!

A little bacteria and mold in my food do not bother me in the least. 

But the chemicals in the felt do worry me. It would be nice to find an inexpensive reusable filter. Cheesecloth seems like it would let grounds through. Perhaps a well-worn/well-washed cloth would work.

I will commence experimentation...

I tried using cheese cloth and it let a lot of grounds through.

Try a new washed handkerchief. I find they work better then cheese cloth I buy them and toss in the wash to remove the starch and things they use on them. A peace of either unbleached cotton or linen also work but you need to hem and wash before use.