A group of students on the Design and Innovation course at the Technical University of Demank is developing the third prototype of a cold-brewing machine.
The Japanese have been enjoying ‘Kyoto cold-brew coffee’, as it is known, since the 1600s.
The traditional way to prepare it involves a set-up featuring three flasks positioned one above the other.
The top flask contains three liters of cold water.
This oozes out through a valve at a rate of around one drip every two seconds, landing on the coffee beans in the middle flask.
At the bottom stands the serving flask that catches the finished coffee.
The process takes about 12 hours.
“In the Japanese system, the valve has to be adjusted manually every two hours because the pressure in the water container changes as the water runs out,” says one of the students Ali Gürcan Özkil.
“And because the water container is positioned at the top of the set-up, there are limits on how large it can be—and, therefore, how much coffee you can brew at a time.”
“Finally, it’s cumbersome to lift into position.”
“So we’ve chosen to place the water container at the bottom and add a pump to send the water up to the coffee beans at the perfect pace,” he added.
“Our design enables us to increase the volume of water to four liters or more, and to make the entire set-up a little lower.”
Cleaning and design
As mentioned above, Ali and his two BSc students—Jesper Alkestrup and Kristian Østergaard Lund—are currently working on
The third prototype of the cold-brew machine has many parts that have to be simple to dismantle and clean every day, so that the entire machine complies with requirements from the food safety authorities.
At the same time, Ali and his team are experimenting with coffee roasters to come up with the perfect coffee, roasted and ground to provide a truly heavenly coffee experience.
Coffee drinkers should enjoy more than ‘just’ the sublime taste, however; the machine itself should be a delight to look at, so Ali is planning to team up with a glass-blower to shape the flasks.
“It’s all about the experience for the user. The machine is a niche product that gels neatly with the current wave of enthusiasm for coffee and the emphasis on ‘slow cooking’,” he relates.
Thus far, the circle of coffee enthusiasts in the Copenhagen coffee environment is so small that rumors about the cold-brew machine are spreading like wild fire.
Ali has not yet come up with a name for his machine, and it may not have anything to do with coffee because he is already experimenting with drawing flavor out of ingredients other than coffee beans.
Hop leaves, for example.
“It tastes almost like Guinness, tasty and refreshing. So why not” he wonders.
Story by Marianne Vang Ryde, Technical University of Denmark
