Like rides on the Coney Island Cyclone or picnics in Prospect Park, iced coffee is a simple summer pleasure. When it comes to coffee, though, there are a multitude of opinions on the best methods for creating the caffeinated beverage. It’s not as simple as pouring leftover Joe on ice, according to coffee expert Liz Clayton.
“Basically because it doesn’t taste good when you do that,” she said. “Pretty much all the methods of iced coffee that there are involve preparing something that’s stronger that, when you add ice to it will be complimentary and will actually, as the coffee melts the ice, produce a more delicious and balanced tasting drink.”
Clayton, whose book Nice Coffee Time was just released in the U.S, explained that “there’s basically two ways to make coffee grounds and water into coffee, and one of them is time and the other one is heat.”
Cold brew coffee relies on time and involves a 10-12 hour soak of coffee grounds in room-temperature water. Clayton uses this method at home and makes sure to set a timer so she doesn’t lose track of how long the mixture steeps. She then filters it twice.
“When you’re using coarse grounds you’re not supposed to have too much small sediment coming through, but you always do have finer particles,” said Clayton, adding that the second filter will eliminate the grit. She noted that brewer’s cloth, sieves, and French press strainers all work as filters. Clayton has been using an almond milk strainer and says it’s fairly easy to clean. Paper filters are also an option but the coffee may take longer to filter through, and the process may require more than one filter.
“[The cold brew method] results in a concentrated liquid that you can pour over ice and a little bit of water to cut it,” she said. “And it’s a very low acid, very sort of mellow flavored style of coffee... A lot of people really prefer that, especially if they have problems digesting coffee. They find that it’s much less harsh on their stomach.”
The method is commonly used by cafes to produce bulk amounts of iced coffee. “If you go to a cafe and they use something called a toddy, that’s what they’ve made you,” Clayton said.
A second method of making iced coffee relies on heat, which brings out the more acidic notes found in coffee. Known as the Japanese method, hot coffee is brewed at a more concentrated strength directly onto ice.
Clayton said that more acidic tasting coffee doesn’t necessarily mean that your coffee will “taste like lemon zest or some craziness that some people find quite disagreeable in their coffee, but what it does mean is there is a lot of nuance. You can get a lot of fruit juice. You can get a lot of what we call sparkle.”
The Japanese method incorporates the amount of ice into the ratio of water to coffee. For any type of iced coffee, Clayton added that it’s important to use clean, fresh ice that’s free of any errant smells.
Below, Clayton provides recipes for both methods to use at home. “There are countless ways to make coffee cold, but here are two of the best,” Clayton wrote about the recipes below. “Note that the measurement systems are different: besides this being an annoyingly common thing in coffee, the fact of the matter is that it's more precise to measure pour-over coffee in weight (and many prefer to brew on a scale), while measuring coffee and water for cold brew overnight is easier to describe in volumes. As for metric versus imperial, I'm half-Canadian.”
Overnight Cold Brew
- 8oz coarsely ground coffee
- 32oz filtered water
- Two ~32oz pitchers, or one ~32oz pitcher and another vessel or bowl of equivalent volume
- A very fine-mesh metal sieve, strainer, or straining cloth such as a brewer's cloth or nut-milk sack
- Clock or timer
Grind your coffee right before the brewing process and put all 8oz of coffee grounds--this is a lot--in the bottom of your pitcher. Fill the pitcher with 32oz of quality, filtered water (not distilled). Make sure all the grounds are saturated (you can stir with the handle of a wooden spoon), cover pitcher, and set a timer for 12 hours. A concentrated coffee brew will be ready after this time.
After the 12 hours have elapsed, pour your coffee concentrate through your sieve or straining cloth, into your secondary vessel. Wash the strainer thoroughly and pour the coffee concentrate back through the strainer and into the first pitcher. Note the fine sediment you've removed the second time around--the second strain is worth it! You now have a concentrated brew base that can be used to make iced coffee for up to two weeks. Serve over ice, and diluted with 1/3 to 1/2 parts water (and/or cream, milk, soy milk, or whatever you prefer) to taste.
Japanese Cold Brew
- Pourover coffee cone such as Melitta, Hario V60, Kalita Wave, etc., and appropriate filters
- Carafe or small serving pitcher that your pourover cone fits onto nicely
- Water kettle
- 30g coffee
- 200g filtered water
- 200g of ice cubes, made from filtered water
Grind 30g of coffee to a slightly finer than medium/filter grind.
Bring your water to a boil, and place ice cubes in the serving pitcher.
With pourover cone on top of ice-filled carafe, place the filter and the ground coffee in the cone and begin pouring your 200g of hot water slowly over the grounds, making sure to saturate.
Begin by pouring in a little less than 1/3 of your water, and wait for the coffee grounds to expand and "bloom" in the cone. Then slowly pour in the remainder of your hot water.
You've made Japanese cold brew! Serve over more ice, as the ice you've already used has melted and become part of the brew concentrate. Enjoy!