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What is flash brew iced coffee?

Flash brewing uses hot water, just like a hot cup. In this technique you less hot water and drip coffee directly over ice. The ice immediately cools the coffee and locks in the coffee flavors. The resulting brew has all the flavors of a hot cup, but with the added advantage that you actually want to drink it on a balmy afternoon.

How does the flash brew method compare to cold brew?

We are generally agnostic about brew methods, each has their place, depending on the desired result. For cold coffee methods, we offer this simple rule of thumb: for those who prefer light roasted single origin coffees, enjoy acidity and tend to drink coffee black, flash brew methods are going to produce a better cup. For those who want a full bodied, low acid cold coffee that is a great platform for milk or cream, cold brew is the way to go.

Flash brew, because of the hot water, will extract more acids than cold brew. This is particularly well suited for light roasted coffees which are selected and roasted for the distinct acidity and delicate aromatics that makes up their origin character. 

Both brew methods make cold coffee but the flavor profile is completely different. Flash brew, because of the hot water, will extract more acids than cold brew. This is particularly well suited for light roasted coffees which are selected and roasted for the distinct acidity and delicate aromatics that makes up their origin character. Acidity can be highly pleasant in a cold drink, so this technique is a great fit for those who like to drink their iced coffee black or with a touch of sugar but no creamer.

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Cold brew recipes typically use more coffee and result in a stronger, more full bodied cup. The cold water extracts less acid so the cold brew is going to be smoother, and a better compliment to the addition of milk. A dark roast with lots of character can be sublime as a cold brew. See our blog on cold brewing if this method sounds like it's more up your alley.

Our flash brew iced coffee recipe

• As a general rule for iced coffee we like to use a 1:10 brew ratio, meaning every gram of coffee is steeped with 10 grams of water.
• A medium grind seems to work best, but should be made finer if the resulting brew is too weak, or coarsened if it is too bitter.
• We’ve found that 200℉ water produces a cup that is not too bitter, but is still well extracted.
• We’ve also found that brewing the coffee directly into a vessel containing ice locks in complex aromatic flavors that are so quickly lost by hot coffee, however using too much ice can easily result in over-diluted, weak coffee.
• So we recommend using about 40% the amount of ice as water.

From there the coffee can be refrigerated and enjoyed with more ice over the next few days, or minutes depending on your coffee habits.

Try it and let us know what you think!