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A high-tech method for producing cold brew coffee that uses ultrasonic waves to extract flavour could cut the time required from 24 hours to just a few minutes.
Cold brew coffee, which is made by steeping coffee grounds in cold water, is gaining popularity because it results in a less bitter drink than traditional methods using hot water. But the technique is also a headache for coffee shops as they need refrigerator space and must allow up to 24 hours to make a brew.
Now Francisco Trujillo at the University of New South Wales in Sydney and his colleagues have found a unique way to quickly extract a cold shot of coffee – by bombarding the grounds with ultrasonic waves. The resulting drink can be ready in less than 3 minutes.
Trujillo says the initial idea for using ultrasound, which smashes up the grounds in a process called acoustic cavitation, was that it might allow the extraction of more antioxidants. This turned out not to be the case, but their initial set up, requiring around £15,000 of ultrasonic equipment, produced a surprisingly good coffee.
“There’s nothing like it,” says Trujillo. “The flavour is nice, the aroma is nice and the mouth feel is more viscous and there’s less bitterness than a regular espresso shot. And it has a level of acidity that people seem to like. It’s now my favourite way to drink coffee.”
www.newscientist.com
Cold brew coffee, which is made by steeping coffee grounds in cold water, is gaining popularity because it results in a less bitter drink than traditional methods using hot water. But the technique is also a headache for coffee shops as they need refrigerator space and must allow up to 24 hours to make a brew.
Now Francisco Trujillo at the University of New South Wales in Sydney and his colleagues have found a unique way to quickly extract a cold shot of coffee – by bombarding the grounds with ultrasonic waves. The resulting drink can be ready in less than 3 minutes.
Trujillo says the initial idea for using ultrasound, which smashes up the grounds in a process called acoustic cavitation, was that it might allow the extraction of more antioxidants. This turned out not to be the case, but their initial set up, requiring around £15,000 of ultrasonic equipment, produced a surprisingly good coffee.
“There’s nothing like it,” says Trujillo. “The flavour is nice, the aroma is nice and the mouth feel is more viscous and there’s less bitterness than a regular espresso shot. And it has a level of acidity that people seem to like. It’s now my favourite way to drink coffee.”
Ultrasonic coffee-maker produces the perfect cold brew in minutes
Cold-brewing coffee can reduce its bitter taste, but it normally takes up to 24 hours as the grounds slowly steep. A new method that involves pummelling the grounds with ultrasound can drastically speed up the process
