Cold Brew Challenge at RGR 2014

The ColdBrew Challenge during the Annual Roaster's Guildwas super interesting. There was a slew of professional roasters, many of whomhave been roasting amazing coffees for decades. However, most of the roastersknew little about how to cold brew coffee. My team, Funky Cold Medina, knewthat if we could get the brewing right that we would have a good chance.

We each were given 5 coffees thatwe could choose to roast and use in our cold brew recipe. After carefullyroasting the each of the coffees we cupped them and settled in on a Guatemalaand Yirgacheffe blend. The Ethiopia was light and slightly fruity while the Guatemalabrought a nice sweetness and the needed balance to the brew.

In the BUNNlab we have been doing a lot of cold brewing over the course of the summer.After a lot of internal testing we think that using a flash brew / cold quenchresults in an expectional cup of cold coffee. This method has been gainingpopularity, pioneered in part by LorenzoPerkins, and being used in a lot of coffeecafes around the US. I was surprised, however, that so few roasters at theretreat had heard of the method. In fact, I think only 3 of the 18 teams usedthis method and two of those teams were in the top 3 finalists.

Funky Cold Medina brewed eachcoffee separately so that we could decide exactly how we wanted to blend afterthe extraction was finished. We used BUNN’s TD3T-Nservers as the brew vessel paired with Toddy’s filter and mesh bag. Theteam loved the ability to have multiple cold brews lined up in a refrigeratoror on a shelf without taking up so much room with a round vessel design. Also,the TD3T-N is easy to clean and the liner can slide in and out for brewing,serving, storage, and more.

 Our recipe was

 14 ounces drip grind coffee

32 ounces hot ( 205°F) water andstir to ensure all grounds were saturated

Steep approximate 2-3 minutes

Add cold water to reach 1 gallon

Brew at room temperature

Taste after 4hrs and either decantor continue to brew for 1-2 more hours. (We stopped at the 5-hour mark)

Surprised at the 4hour mark fordecanting? I was, too, initially until we did a lot of tasting and measuring atBUNN. We found that most cold brews began to plateau in terms of extractionaround 4 hours. There was little or no increase in extraction between the 4-and 5-hour marks on the brews we did in our BUNN lab. However, there wereslight taste differences but most of the time we preferred what we wereexperiencing on the shorter brews.

After the brew, we blended a fewdifferent ratios at full strength and settled in on a 50/50 blend. I have tosay: this was the sweetest, most balanced iced coffee I’ve had. Funky ColdMedina’s overall score was 9 points lower than the winner and we came in at 2ndplace! (Not bad out of 18 teams).

TDS samples of all the submittedcold brews revealed a pretty tight range. People used different methods, mostwere TODDY, but a few were the "slow drip" style where ice or icewater is slowly dripped over a bed of grounds. The average was 2.55 while themedian was around 2.62. My team's brew was 2.18.

How do you cold brew? Sound off on Twitter orFacebook or share in the comments below.