Cold brew: Coffee's hottest new trend?

You probably like your coffee hot, but coffee expert Brett Johnston tells Metro Morning that java junkies are warming up to cold brew, which is different than iced coffee.

Don't call it iced coffee. This stuff takes up to 24 hours to brew

Cold brew coffee differs from iced coffee in that it's brewed with cold water over a long period of time, as much as 24 hours. (Pilot Coffee Roasters/Instagram)

Is cold brew the next hot coffee trend?

For Brett Johnston, a coffee specialist and head of innovation at Toronto's Pilot Coffee Roasters, coffee doesn't always have to be served hot.

Johnston appeared on CBC Radio's Metro Morning on Wednesday to talk about cold brew, a coffee trend that's starting to generate a lot of buzz among java aficionados.

What is it? First off, don't call it iced coffee. That's often just a half-espresso poured into milk with ice cubes and served diluted and cold. This is coffee brewed in cold water for long periods of time, often between 12 and 24 hours.

Pros and cons The brewing takes longer with cold water, but Johnston says the process creates a different flavour profile, with fewer acids.  "You essentially exchange temperature with time," he said.

How is it made? The most common process is immersion in which ground coffee brews in a bucket of cold water. In one concoction he serves called "nitro cold brew," where the keg is pressurized with nitrogen.

So does this mean more caffeine? Although cold brew coffee is often more concentrated, the caffeine content would be the same so long as it's diluted to the same strength as regular coffee. 

OK — Maybe in July, but no one will drink cold brew in February, right? Not so. Johnston says more and more people are starting to enjoy cold brew, even on cold days. He says people step up to his coffee bar for nitro brew year-round.

But isn't this really just a fad? Johnston says no. Coffee nuts are always trying to push the boundaries but he says the cold brew trend is starting to catch on. "I strongly feel that cold brew is going to become an established way of enjoying both commodity and specialty coffees. It will continue to break out and become more established."

Click below to listen to the full interview.