Thinking I was being clever and thrifty one day, I put leftover coffee from my percolator in a glass container and stuck it in the fridge. Voilá, iced coffee!
It tasted bitter and flat, and for good reason. That's what happens whenever you let a cup of coffee sit around after 45 minutes. It's not the way you make iced coffee.
So what is? There's a debate about that, cold-brewed versus hot-to-ice brewed, or what Counter Culture Coffee's Peter Giuliano calls the "Japanese iced coffee method."
Coffee specialists will tell you that coffee needs hot water between 195° F and 205° F to unlock the solubles and aromatics in ground beans. Cold brew methods operate by substituting time for temperature.
Giuliano blogged that using cooler water will incompletely dissolve those coffee solids, leading to a beverage that's "low-end, dead, and without aromatics." He said hot brewing double-strength coffee directly over a container filled with ice extracts those solubles, while quick-cooling the coffee to lock in ephemeral volatiles and halt oxidation, which makes coffee bitter.
But Teresa von Fuchs, the coffee and espresso consultant for Dallis Bros. Coffee, thinks cold-brew is unfairly getting a cold shoulder: "When you taste them side by side, I think both ways are equally good. Just different."
She met me at Root Hill Café in Gowanus, in Brooklyn to demonstrate. We sampled a Colombian coffee, Cerro del Reyes, made two ways -- cold-brewed, and hot-to-ice brewed. We sampled them at two temperatures, room temp and with ice, the way you'd get it if you ordered an iced coffee.
Von Fuchs made the cold brew in her French press at home. Instead of the recommended hot brew ratio of 1 ounce of coffee to 16 ounces of hot water, von Fuchs used one ounce of coffee to 12 ounces of room temperature water.
"I agitated it (meaning, she gave it a good stir), and then just let it sit -- 12 to 24 hours -- depending on the size of the grind," she said. "Eighteen hours is a prime dwell time."
Her cold-brewed version was cloudy and light brown: "It wasn't passed through a paper filter, so you can see the oil, see the particles."
The hot-to-ice brewed version was much darker and clearer, having been filtered through a paper cone.
We slurped the room temp versions first. I got hints of caramel and vanilla, with a fruity burn at the finish. Von Fuchs described it as "cherry skin."
The dark, hot-to-ice version of the same coffee had a big chocolate taste. It was sweet and fuller-bodied, "juicier," as von Fuchs put it.
Both were very smooth, with a tart, fruity finish.
"To me, it's obvious it's the same coffee," said von Fuchs.
Next, the iced samples. For me, ice ruined them both. They lost a bit of their character. I thought the hot-to-ice brewed version stood up better to the cubes, but still, it was, well, watered down.
If ice made iced coffee less pleasurable for me, what would milk and sugar do? That's the way most people take their coffee, including me.
Von Fuchs, a purist, made a face. Coffee, she said, has its own sweetness: "When you add a little bit of sugar to coffee, you actually perceive it as salty until you add enough sugar to drown that out."
We added a little simple syrup to her cold-brewed Colombian. She was right -- it tasted sharp and salty and bitter. We added a few more drops, then sipped. Now the initial taste was all sugar, with a little hint of coffee, raising its hand at the back of the class, trying to get my tongue's attention.
Holy cow, I may turn into a black coffee drinker yet.
My view? I prefer the hot-to-ice brewed coffee better. But I can see von Fuch's point. Both methods made a solid glass of iced coffee, expressing something different about the bean in the same way that different hot brewing processes -- pour over, percolator, espresso -- do. (This, by the way, will be the topic of an upcoming post ... if I can recover enough from all the caffeine to type straight!)
There's all sorts of info on the web about cold-brewed and Japanese iced coffee. Check out these posts at America's Test Kitchen Feed, I Need Coffee, Clive Coffee and The Kitchn.
Do you make iced coffee at home? How do you do it? Which method do you prefer? Let me know, leave a comment below.