What’s all the Buzz About Cold Brew?

Iced CoffeeLately, everyone (and mostly that means the e-media) has been buzzing about cold brew coffee. It seems like it’s a topic making headlines almost as often as politics these days.

So we thought we’d talk about what it is, why you might want to use this brewing method, and why you probably don’t need to (but certainly can) use it for our Hawaii’s Local Buzz coffee. You can take a look here for some other ways to make iced coffee to cool you off in the dog days of summer. (By the way, our dogs object to that phrase and consider it to be politically incorrect.)

First we need to understand what makes coffee… well, coffee. The delicious liquid that gets us up in the morning and adds a nice finish to a fabulous meal happens when we extract the flavor of roasted coffee from the roasted beans into water. Traditionally, as you know, we use hot water to coax all those flavor molecules out of our ground coffee and into our pot or cup. Sometimes, as with espresso, instead of using water we use pressurized steam to force, rather than coax, those molecules out.

So what is cold brew? Well, it’s a method of brewing coffee, and usually a coffee concentrate, that doesn’t involve heat. Technically, with the cold brew method you steep your coffee rather than brew it, soaking ground coffee in (usually room temperature) water for a relatively long time (up to 24 hours).

The benefits of cold brew are:

  • First, it starts out cool so it makes great iced coffee without the degradation in flavor that can happen if you chill coffee that was brewed hot.
  • Second, if done correctly, cold brew coffee should be less bitter and less acidic than coffee made using heat-dependent brewing methods. Because our Hawaii’s Local Buzz coffee is already very low acid and not bitter, it should be less necessary to use this brewing method for our coffee than it would be for other beans.
  • Third, cold brew creates a concentrate that can be stored in the refrigerator for a week or more (or frozen into ice cubes for longer storage), so it’s easy to have cold coffee on hand for those moments when you crave an iced coffee RIGHT NOW! You can store hot-brewed coffee in the fridge for iced coffee as well, but you shouldn’t store it more than a few days, as hot-brewed coffee can get a sour taste or aftertaste if stored in the refrigerator for a long period of time.

Although it takes a long time to get from coffee grounds plus water to finished cold brew coffee concentrate, most of that time is spent waiting rather than actively preparing the coffee. And, while it’s possible to complicate the process and make it sound very difficult to get right, it’s actually almost ridiculously easy to do. The important “tricks” of making great cold brew coffee are (in no particular order)…

  1. Start with great coffee. The flavor of coffee will only ever be as good as the beans you use, and while it’s true that cold brewing can get you a better cup of coffee from lesser beans than hot brewing, the best coffee (brewed cold or hot) will still come from the best beans.
  2. Start with great water. This is also true for making great hot brew coffee and it’s something people often don’t think about. You want to use a nice, filtered, pure water that has no unpleasant taste. If the water that comes out of your tap isn’t fabulous to drink, don’t use it for your coffee.
  3. Start with coarse ground coffee. This is a significant difference from the way you would make drip or pour-over coffee – for those brewing methods you want to use a nice fine-ground coffee. For cold brew, like for French Press, you want to use a coarse grind. When you use a French Press you use coarse ground coffee mostly to minimize the chance you’ll get coffee “sludge” in your cup. When you make cold brew coffee, however, you want to be sure to use a coarse grind so that the coffee doesn’t over-extract as it’s steeping. (And it does make the “straining” part of the preparation process less messy as a nice side benefit.)

As with any brewing method you’ll want to experiment with the ratio of ground coffee to water that you use, settling on whatever seems to make an end product suited to your own particular taste. A good starting ratio is 1 ½ cups of water to 1/3 of a cup of coarse ground coffee. (To make larger quantities simply maintain the same water to grounds ratio.) Put the coffee grounds in a jar (a Mason jar can work very nicely), add the water slowly, stir gently just enough to evenly wet the coffee grounds, cover the jar, and let it sit for 12 – 24 hours.

When you’re ready to decant, take a fine mesh strainer and pour the liquid through to strain out the first large “clump” of coffee grounds. Then rinse the strainer, add a large paper coffee filter (or cheesecloth if you want to get fancy) and strain the liquid again to remove the finer particles of coffee that will remain. And shazam – you have a nice cold brew coffee concentrate. Refrigerate for up to 2 weeks or freeze for longer storage, and then thin out the concentrate with water or cream to taste.

And remember that you can take those coffee grounds right out to your garden or compost pile – they do wonders for plants.

8 thoughts on “What’s all the Buzz About Cold Brew?

  1. MJ

    this is exactly how I’ve been making cold brew for 5-6 years now. I’d like to stress using a GLASS jar or bowl for the cold-brewing part. You don’t want metal or plastic for obvious reasons. Well, maybe not so obvious? No metal because it might impart flavor, and no plastic because the acidity of the coffee could extract yucky chemicals from the plastic. After the first rough sift with a kitchen sieve, I run it through a coffee filter inside a funnel set into a water glass. Two of those going at once makes pretty good time. I start with a clear glass mixing bowl and the end result is stored in a 2Q glass pitcher in the frig for about a week.

    1. Lili Rodriguez Post author

      Thanks for adding the extra tips. Have you ever made cold brew from our Hawaii’s Local Buzz coffee?

  2. LauraRose

    Mostly we just use yesterday’s coffee remains for iced coffee, but the few times I have bothered w/ cold brew I used a French Press and it seemed to work great. I poured it into a jar to put it in the fridge.

    1. Marilyn Bennett

      You say that you use yesterday’s coffee grounds for iced coffee? What process do you use? I love iced coffee, but I’ve always used fresh grounds.
      Thanks for the info!

      1. Hawaii's Local Buzz Post author

        Aloha Marilyn,

        I think what LauraRose meant is that she uses the coffee she brewed “yesterday” for iced coffee today — not the grounds. We sometimes do that (in our home) as well. If there is leftover coffee after everyone has had their morning cup(s), we’ll refrigerate what’s left and use it for iced coffee the following day. We don’t keep cold coffee in the fridge more than a couple of days past when it was brewed, and we often use coffee ice cubes rather than ice cubes made from water so the ice doesn’t water down the coffee.

        Hopefully that made sense.


        1. Marilyn Bennett

          Ahh! Ok. I was a little confused… Thanks so much for clearing that up!
          And I agree, Hawaii Buzz coffee is so good and low in acid that there is no need to use Cold Brew!

  3. MJ

    SO I thought I’d share my new discovery. The straining part of the job takes a while. Well, I sew (with a sewing machine), so I decided to try sewing two filters together and putting the ground coffee into this ‘packet’. I sew it closed and dunk it into the bowl of water. Works great! In fact I tested it also with four filters instead of two (two on each side of the coffee) because sometimes the filter packet rips and the coffee spills out. Now all i have to do is fish out the coffee packet.

    Yes, a French press works too, but I like to make a big enough batch to last a week.

    1. Lili Rodriguez Post author

      Thanks so much for that tip! Unfortunately I can’t sew a stitch (I know… I’m suitably embarrassed) but it sounds like a great idea and hopefully will help those who actually can sew. 🙂


Leave a Reply

Your email address will not be published. Required fields are marked *