Gift Lab: Can You Do Cold Brew Coffee at Home?

Abstract:

Coffee is good. Hot coffee when it’s still hot out is not so good. Will the Cold Brew Coffee Maker save me?

Background:

I am one of about 2/3 of adult Americans who will have a cup of coffee today at work. But in the dog days of summer, hot drinks aren’t really what I’m thirsting for. Unfortunately, every time I’ve tried to make iced coffee it came out bitter. It usually just sits in my fridge as a testament to my failure for a few days before I toss it.

Maybe I’ve just found 1,000 ways not to make iced coffee.

With that in mind, I set off with the Cold Brew Coffee Maker to try one more time.

Before I picked up this coffee maker I had no idea what “cold brew” meant. As I learned from the instructions, it’s a method of brewing where cold water is slowly percolated over ground coffee. The cold water prevents the bitterness of the beans from flowing into the retaining jar, and the slow pace allows plenty of flavor to end up in the final product. It takes a while, and the longer you allow it to take, the more flavor will end up in your cup.

Hypothesis:

My null hypothesis: I can’t make a decent cup of iced coffee.

My alternative hypothesis: I can (if I use the right tools).

Experimentation:

A handy illustrated insert easily explains the setup.

First, I filled the center compartment up with enough medium ground coffee to reach the “only this much” line. It took me three scoops; the instructions say that’s about 2/3 of a cup.

On top of the coffee I placed a little white filter paper (included) and dotted it with water. This helps diffuse the water as it drip-drops down across all the beans, not just those directly under the nozzle.

There’s a rubber seal and metal valve control regulating the water from above the grinds to the retaining jug below. It’s not hard to press in, but you’ll want to make sure it’s sealed so the water drips – not pours – over your grinds.

The ice and water sit in a reservoir on top. Again, I used the “only this much” line; the instructions say it’s about 24 oz.

To start it brewing, slowly adjust the metal valve control rod to allow water to begin dripping down onto the ground coffee. The instructions suggest that you allow it to flow at one drop per second, but as your patience wanes you might find yourself edging it faster. I found the best approach is to set it and walk away.

It usually takes about 3-5 hours to finish brewing. Because the weight of the water above helps the water to flow down, you might find it necessary to edge the valve open a bit more during the course of the brew.

Conclusion:

I reject my null hypothesis, and find that I can, in fact, make iced coffee. I admit I was a bit skeptical about using cold water to brew coffee. And in one attempt I didn’t appreciate how important the “slow” part was to the brewing process (pro tip: don’t fully open the flow valve. You’ll end up with water that looks like tea and tastes like your impatience).

Cleanup and Storage:

I’ve been using a large glass jar to keep the coffee after I brew it because it’s normally more than I want at once. Since the entire maker is just two glass cylindrical pieces, cleanup is a breeze. The coffee grinds just fall out the bottom of the center portion and the entire thing cleans up in a snap.