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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

#81

Post by bunderbunder »

nkozyra wrote: post #67
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 find that heating cold brew reintroduces some of the flavor of hot brewed coffee, though I've never been able to pinpoint a mechanism for it.

Speculation: A lot of it is that chemicals that contribute to flavor are more volatile at higher temperatures.

The same things happens with beer. Many traditional and craft beer styles are intended to be served at a higher temperature than what it will be right out of the refrigerator, and you really do get more (and, to my palate, better) flavor out of them if you let the bottle warm up on the counter for a while before you open it.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#82

Post by [deleted] »

iancmceachern wrote: post #21
triceratops wrote: post #14

Earlier quoted context omitted.

> The system connects a bolt-clamped transducer with the brewing basket via a metallic horn – transforming a standard espresso filter basket into a powerful ultrasonic reactor. Now it can be done without shelling out $695 for a dedicated machine. That's progress. I wouldn't be so dismissive.

But you have to shell out $10k for a commercial ultrasonic welder from Branson, etc. Just the horn they show in the paper probably cost $6k to make. I wouldn't be too dismissive.

[deleted]

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#84

Post by jmilloy »

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…

Everything you say makes sense, with the exception of your expectation not to pay extra for an unusual order (for that cafe). Consider if I asked for my salad to be roasted, and balked at a surcharge on the grounds that they also have roasted brussel sprouts! I don't think it's up to you to decide what orders fit into their flow and which cost extra. I'm glad you found the places that will make the coffee the you like.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#85

Post by dahart »

nkrisc wrote: post #60
csmpltn wrote: post #53

Earlier quoted context omitted.

This is an extreme form of coffee hipsterism. “Cold brew, but steamed please”. Brother, this is starting to get ridiculous.

It’s no different than drinking an iced coffee drink that was made from coffee brewed traditionally.

That’d be true if putting ice in coffee reduced its acidity. Heating cold brew brings a lower acidity liquid up to a nice warm good morning temperature.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#87

Post by Y_Y »

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!

Pretension is nine tenths of the law

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#88

Post by karaterobot »

triceratops wrote: post #14
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…

> The system connects a bolt-clamped transducer with the brewing basket via a metallic horn – transforming a standard espresso filter basket into a powerful ultrasonic reactor. Now it can be done without shelling out $695 for a dedicated machine. That's progress. I wouldn't be so dismissive.

> However, engineers from UNSW have now developed a new way to make cold brew coffee in under three minutes – just like a regular hot brew – without sacrificing on the taste experience.

I think the commenter you're responding to was calling out the use of the word 'new' (which is used five times in the article) to describe the process, when it's evidently not new at all. The commenter didn't say anything about the price point, and neither does the article.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#89

Post by ackfoobar »

dahart wrote: post #76
csmpltn wrote: post #53

Earlier quoted context omitted.

This is an extreme form of coffee hipsterism. “Cold brew, but steamed please”. Brother, this is starting to get ridiculous.

My doctor recommended cold brew for lower acidity, because hot brew is bothering me. Cold brew is just a brewing process and has nothing to do with serving temperature. Cold brew has never meant served cold. So what, exactly, is ridiculous about warming up cold brewed coffee? I like my coffee hot, like a lot of people, and I’d like it if I can keep drinking coffee and don’t have to stop due to the acidity.

It might be obvious but I have to ask, is that a stomach problem?

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#90

Post by vincentrolfs »

hammock wrote: post #72
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.

>the harder you press, the more bitter it will come out Huh? I don't plunge until after it brews, and the purpose of the plunge is just to keep the water out of the grounds from that point forward, to (essentially) stop the brewing process. Or so I thought

I agree with your confusion, are we all talking about the same thing?
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