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- Hacker News
- Someone get James Hoffmann on the line right now.
- The American tech video is still surprising me.by intended
- I will wait for his blind testing before homebrewing this one.
Might be a new meta for iced lattes.
by willis936 - mmm.. what about pressure? the real espresso need pressure... is not just hot water. is the pressure of the expanding water that pushes it... not sure it would be the same stuff lolby Febriss33
- There is still pressureby cush
- But people want to drink coffee/espresso hot, not room-temperature. So you have to heat the water afterward anyway. I'm not seeing that much potential for energy savings here, unless you're comparing setups with large boilers inefficiently used for small amounts of coffee.by fabian2k
- I usually forget about my coffee anyway until it's cold.by ma2kx
- To be fair, precedent has already been made with cold brew.by exitb
- > But people want to drink coffee/espresso hot
An awful lot of people drink iced espresso drinks these days. Room temperature (or below) brewing would make a big difference to the dilution in those drinks.
by swiftcoder - They explicitly mention large scale producers for mixed drinks as a massive target audience. E.g. iced coffee manufacturing will be heavily impacted, they would normally need to heat the liquid, extract the coffee and then cool it back down.by tjcvirage
- According to the article they see the main use for industrial scale production of coffee/espresso based drinks, in that regard it does make sense. For home use not so much even if there could be some niche market for cold espresso drinks at home, using less ice would allow for less dilution and faster than prepping and then refrigerate the coffee. I sometimes put concentrated ice coffee into my whey/oat shakes, but this is indeed very niche use even for me.by hultner
- I always find great podcast suggestions in HN threads about a topic. Here is me giving back to the community, coffee history and nerdy detail. https://podcasts.apple.com/us/podcast/ologies-with-alie-ward...by bicepjai
- > For filter coffee, however, the ultrasound-brewed version performed even better: participants significantly preferred it overall, particularly rating its bitterness as more pleasant.
I'm surprised by this, my assumption from hot coffee vs cold brew was that since the water isn't hot, there wouldn't be as much bitterness? Or maybe I'm reading it wrong and it's why they prefer it, because it's less bitter?
by m-p-3 - Then just get a lighter roast and don't over extract? Also if it's espresso get rid of the crema. Looks geat, tastes awfully bitter.by petre
- It immediately brings to mind that YouTube video where a guy was making whiskey out of vodka and oak chips in an ultrasonic bath.by cocodill
- This sounds awful. I’m an espresso snob and caffeine isn’t even on my list of why I love it. It’s like they complete ignored what makes a good shot and focused on one element.by supertroop
- I'm sure someone like Giovanni Gaggia will improve it a bit, to the point there is nothing to improve anymore.by petre
- I'm curious why you focused on caffeine when the article says their study found that people tasted no differenceby cush
- I'm also an espresso snob and got the complete opposite take. The idea of decoupling grind size and brew time from yield is super interesting. The only other device I'm aware of that does this is a pressurized portafilter basket but that's only there for people that don't have good enough grinders.by duped
- > “And when we gave our ultrasonic espresso to 100 regular coffee drinkers in a randomised test, they could not tell it apart from a normal espresso.”
I like the ritual of it, for sure, but I'm not sure that's what makes it a good shot?
by ceejayoz - What exactly is the innovation here compared to the press release from two years ago?[1]
[1]: https://www.unsw.edu.au/newsroom/news/2024/05/Ultrasonic_col...
by erikgahner - Different kind of coffee drink being prepared; espresso vs cold brew.
(You might quibble whether it's actually espresso if there's not pressure and it's extracted cold; but it's closer to espresso in strength.)
by klausa - Does this work with cold water? Because if so, my iced espresso drinks are crying out for it
Where's James Hoffmann when you need him?
by swiftcoder - Although, tbf, I forgot he did a video on ultrasonic barrel aging[1]by swiftcoder
- Wonder why they chose to stick with the portafilter form factor rather than something custom for the method. Perhaps it just fits the task well and they don't need to change, or they want to preserve the look of an espresso machine. Though, if the water is room temp, they only really need the pressure, which doesn't need the entire machine. Seems pretty cool.
Edit: The article shows that they chose this method specifically to use the basket, and the basket allows for the vibrations they need. The other conveniences of the basket form factor also come into play; reloading, cleaning, etc. and don't need reinventing or retraining. Cool stuff. I wonder whether they'll remodel the machine around the basket and remove what's not needed if this becomes a product.
by nusl - Consistency in output - this is a standard test model to replicate entire existing system and then apply changes components of the system to test a theory.
- This is really cool, I have so many questions! What's interesting to me is they only replaced the hot water part of the equation, and the system still requires high pressure.
How does ultrasound affect flow rate? Do fines sink to the bottom of the puck and choke the shot?
There is a new movement happening, especially in lighter roast coffees, where we're finding that more balanced extractions (less bitterness/acidity/acridity) are happening at lower pressures, even going so far as grinding so coarse that the puck offers zero resistance - effectively making the pump the limiting factor for flow rate. Light roast coffee is much less porous and more hydrophobic.
I wonder if adding ultrasound would allow light roasts to yield more extraction in general, maybe even keeping the high temperature. Or, would adding ultrasound allow a finer grind size and more resistance without adding the harsh flavors of a high-temperature shot.
So many experiments to be done!
by cush - > Both espresso samples were served at 22 °C to ensure a fair like-for-like comparison […]
> It is noted that espresso is normally consumed hot and has transient sensory attributes that are temperature- and time-dependent. Hence, serving espresso at 22 °C will alter its sensory characteristics.
This is a weird test, coffee get’s so much worse when cold. So people can’t distinguish between two bad coffees.
by jurf - "Good" (well-extracted) coffee is still relatively good when warm, especially compared to "bad" (over-extracted, or under-extracted) coffee. That said, many believe that the optimal temperature for serving coffee is 50-60 degrees celsius (122-140 degrees fahrenheit).by nickff
- > coffee get’s so much worse when cold
Coldbrew is a thing and done right it brings out a refreshing sweetness. Also iced coffee. Bad coffee is bad hot or cold.
by hylaride