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Cold brew coffee in 3 minutes using acoustic cavitation

unsw.edu.au

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Re: Cold brew coffee in 3 minutes using acoustic cavitation

#251

Post by solardev »

ChrisMarshallNY wrote: post #247
dc96 wrote: post #241

Earlier quoted context omitted.

Looks like the comment you replied to links to a Jura as well

Yeah. My friend has one that cost around 3 grand. The main issue that I would have, is maintenance. I would guess that it would need a fair bit of cleaning. I just use a fairly basic Braun Melitta filter, and it does great.

It's got a decent self-cleaning cycle. Every month or two, it'll ask you to put in a cleaning tablet (about $2 for the OEM version, or there are cheaper generic ones). It goes through an internal cleanse and poops out a slop of muckety muck. I put on soft yoga music for mine, but that's optional. Ten minutes later it's ready to use again.

About half as frequently, it'll also ask you to put in a descaling tablet. Similar process.

Beyond that, day-to-day, it can make about 8 shots of espresso before the grounds hopper is full. You just dump it and rinse it in the sink (no need for a thorough wash) and it's ready to use again. Less cleanup than a regular drip coffee maker (no filters to deal with, no grind dust to rinse/brush, no glassware, nothing to dry).

It's super convenient. The main downside is really just taste. I tried to do a blind taste test with my coffee snob friend (he's the kinda guy who measures everything down to the milligram and gives his grounds acupuncture before sending them to the spa). We used the same bag of beans, same water, same cups, etc. His came out with a layer of fine oils and sparkling foam. Mine looked like someone opened a dishwasher prematurely. We couldn't even get to the taste test part because you could smell the difference with your eyes closed. And I had a clogged nose that day.

Maybe the $3k Jura is different, but my janky little unit is definitely a poor man's machine – the hand-me-down Civic of superautomatic coffee makers. I'd buy it again in a heartbeat though.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#252

Post by King-Aaron »

solardev wrote: post #225
dahart wrote: post #17

Recently I discovered that many coffee shops, maybe half in my sampling of a couple dozen in different cities, are selling cold coffee (brewed hot, then refrigerated) under the name cold brew, and even the ones that actually cold-brew them seem to be under the impression that it needs to be served cold. I was laughed at in one hipster joint for asking for a steamed or warmed cold-brew, and another one initially refus…

This is why I love my fully automated luxury mediocre espresso maker ( https://www.seattlecoffeegear.com/blogs/scg-blog/jura-a1-rev... ). I push a button, it grinds the coffee and does stuff inside that I can't see, then moments later I have a perfectly average cup of something resembling burnt bean soup. I don't know whether it's megasonically brewed or absolute-zero infused or just wet caffeine pills. Sometimes it'…

I like the cut of your jib.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#253

Post by mianos »

papertokyo wrote: post #220
mianos wrote: post #211

"Ultrasounds can be applied to several areas across the food industry including drying, extraction, emulsification and crystallisation – making the process faster and more efficient.", .. I think they have the tense wrong. It should read "Ultrasounds are now commonly applied .." People have been doing this sort of thing for years. I have an ultrasonic tub for extracting flavours into ethanol. I didn't invent it, peop…

The innovation here is integrating the tech into a home espresso machine package. I do wonder if the sound is any less awful though. Does the ultrasonic tub enable better extraction at lower proof or are you using it purely to speed up the maceration process?

The ultrasonic tub, (Vevor LOL, like everyone else gets for their bike parts), speeds up the process, specially oak shards.

For comparison, I also have a Soxhlet apparatus. As the extraction is boiled in the bottom with the recycling solvent it does not make the best flavours but it's the fastest way to get stuff like cinnamon.

Between a longer time, soxhlet and ultrasonic, the ultrasonic gives flavours as smooth as a longer time without the wait. (The ultrasonic bath heating up is still a problem so I have to cycle it).

Time beats both.

I think a short path soxhlet maybe be as good. My setup is a bit fragile for a good vacuum though.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#254

Post by kibibyte »

ada1981 wrote: post #58
lamename wrote: post #32

Earlier quoted context omitted.

Thank you for saying this. When cold brew first came out, it was promoted as a brewing process that resulted in smoother (I'm guessing lower acidity) tasting coffee. Heating it up seemed natural, and its use in iced coffee seemed simply opportunistic. (In my experience at least). Then it quickly caught on as a novelty, with nitro et al, and when I tell people I drink cold brew warmed I get looks of confusion or turne…

The more complex, expensive and counter intuitive your morning coffee, the better! 90% of the experience is looking cool!

You poke fun at it, but great irony is that a lot of knowledgeable coffee people started poking at all the techniques recently and we've learned that almost everything towards the showy complicated side of it are completely not worth thinking about or will have worse results. Osmotic pouring looks neat but will underextract anything that isn't dark. 4:6 is still questionable over most simpler 1-2 pour techniques. That showy thing of raising the kettle up and down a lot also will underextract.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#255

Post by AdamJacobMuller »

solardev wrote: post #251
ChrisMarshallNY wrote: post #247

Earlier quoted context omitted.

Yeah. My friend has one that cost around 3 grand. The main issue that I would have, is maintenance. I would guess that it would need a fair bit of cleaning. I just use a fairly basic Braun Melitta filter, and it does great.

It's got a decent self-cleaning cycle. Every month or two, it'll ask you to put in a cleaning tablet (about $2 for the OEM version, or there are cheaper generic ones). It goes through an internal cleanse and poops out a slop of muckety muck. I put on soft yoga music for mine, but that's optional. Ten minutes later it's ready to use again. About half as frequently, it'll also ask you to put in a descaling tablet. Simi…

Kind of interesting.

I have the Jura Giga 5 and I would say it produces coffee which is better than I can get in any chain store, and, better than the average specialty shop as well. Obviously there are some specialty shops which produce excellent coffee which is better than the Jura, but, not by a massive margin. Interesting that you find the A1 to be much poorer in quality, or my pallet just sucks. Either way I fully agree with you that having "push button, make coffee" is fantastic, I don't want to fiddle with scales and worrying about blooming my coffee grounds for 14 seconds at 92c before brewing with water at 90c. Push button. Make good coffee.

The other "maintenance" item I've noted after having this machine for >10 years is that every 5 years or so it breaks and I have to send it back to Jura.

Their warranty service is a flat-rate $500 and they either repair yours or send you a refurb unit, for something which I spent almost 5k on, I'm very happy that they seem to have the option to basically keep the Jura working forever if I want.

The Giga 5 prefers to listen to the Spotify "upbeat pop music" playlist when I run the cleaning cycle FYI.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#256

Post by dahart »

kjkjadksj wrote: post #197
dahart wrote: post #17

Recently I discovered that many coffee shops, maybe half in my sampling of a couple dozen in different cities, are selling cold coffee (brewed hot, then refrigerated) under the name cold brew, and even the ones that actually cold-brew them seem to be under the impression that it needs to be served cold. I was laughed at in one hipster joint for asking for a steamed or warmed cold-brew, and another one initially refus…

I wonder if you can deal with the acidity issue in a quick and dirty manner by just throwing in some baking soda into your grinds and brewing hot?

Okay this is a totally wild and hilarious coincidence, but I came home tonight and told my wife about this thread. Turns out that, today of all days, without knowing I was ranting about cold brew on HN, she did a careful home experiment with her coffee using baking soda, so I can report on what she found. She has suffered me complaining about fake cold brew and rude baristas before, but it’s been months since we discussed it. We do have some pH test strips sitting around from my investigations into different brewing methods, and she used 4 of them doing this experiment twice.

For each experiment, she made 2 cups of coffee, using 1 scoop of grounds (0.25 oz) to make a pour-over with 8 oz water heated to 200 degrees Fahrenheit for each cup. In one of them she added 1/16th teaspoon (which is a tiny pinch) of baking soda to the grounds before pouring the water over them. In the other cup, it was only grounds with no baking soda. She said she could see the water foaming in the cup with baking soda. She reported that there was no noticeable negative flavors at all, no hint of baking soda taste, the coffee made with baking soda was as good as the control, perhaps slightly better because it was less acidic. For the pH measurement, she measured a pH of 6 for the normal coffee and a pH of 8 for the baking soda added cup — it actually made the coffee slightly alkaline! PH of 6 sounds like a pretty weak coffee, I was usually getting a pH of 5 IIRC. PH strips are a pretty blunt measure and don’t give you fractional pH values, but she showed me the strips and I can confirm her conclusion. The 2nd experiment was the same setup, and the result was identical.

When I read your comment earlier, I thought it was a good question, but assumed baking soda would change the flavor negatively. I’m surprised to hear that it totally works, so I think you have a good idea. I might even consider making this my routine if it works that well. Now I’m curious if you can sprinkle in a tiny pinch of baking soda into an already brewed coffee and reduce acidity without damaging flavor…

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#257

Post by AdamJacobMuller »

lytfyre wrote: post #215
this_steve_j wrote: post #132

Earlier quoted context omitted.

Perhaps the Yama cold brew tower CDM25 is the device you saw. It is used at many fine establishments including my kitchen, and I also have the smaller CDM8. The numbers 8 and 25 correspond to the number of cups of diluted 1:1 cold brew that it produces in a single cycle (6-12 hours). https://yama-glass.com/collections/cold-brew-towers

If any HNers are looking for a cheap entry point into the style without spending $250+ on a beautiful bunch of laboratory glass ware, there's the puckpuck[1], which sits on top of an aeropress and turns it into functionally the same device as the Yama towers - slow controlled valve dripping cold water at a controlled rate onto a bed of coffee and a paper filter over the course of hours. I've found it a nice way to pl…

I have a toddy, produces excellent quality cold brew.

https://www.amazon.com/Toddy-THM-Cold-Brew-System/dp/B0006H0...

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#258

Post by hobolord »

peteforde wrote: post #13

Funny thing is that I'm currently drinking cold brew that I prepared on my acoustic cavitation brewer. It's called Osma Pro. The company that made it sadly did not survive, and they took a lot of heat (no pun initially intended) for the price point and various complaints about how it worked. https://www.engadget.com/osma-pro-cold-brew-coffee-machine-r... Luckily, mine works great and I like it a lot. I use it every m…

There's also this ultrasound company that sells lab equipment, but has a cold brewing via sonification page as well https://www.hielscher.com/ultrasonic-extraction-of-caffeine-...

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#259

Post by throwaway984393 »

dhritzkiv wrote: post #187
seanhunter wrote: post #6

This is awesome in an overengineered way, but if you want to make cold brew the normal way it's very easy. Basically you make it using a cafetière/French press/Bodum[1] using cold tap water in the fridge overnight (probably put some cling film over it), then press it and run it through a drip filter. The secret (if there is one) is to use fine ground coffee like you would use for an espresso rather than coarse ground…

One thing I'll mention is that cold brew doesn't need to be put in the fridge to "brew". It can be left out on the counter at room temperature. As a result, this takes the brew time from 24 hours to about 12 hours.

[dead]

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#260

Post by base698 »

senkora wrote: post #42
arijun wrote: post #19

Earlier quoted context omitted.

If you use a French press for cold brew, be aware that the harder you press, the more bitter it will come out. I use a $5 nut milk bag instead, it lets me brew way more at once; I do 1/4 kilo grounds with 2 liters of water. It also has the benefit of reducing cafestol, which makes it healthier, according to some.

> It also has the benefit of reducing cafestol, which makes it healthier, according to some. I often filter my french press cold brew after-the-fact with a paper filter to achieve this.

Isn't the paper filter supposed to strip flavorful oils? Which negates using a French press?
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