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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

#271

Post by kimixa »

rhaps0dy wrote: post #126
janalsncm wrote: post #73

Earlier quoted context omitted.

It’s a market for lemons at this point. Unless you can see an expensive apparatus or observe them soaking the coffee, there’s no way to know if it’s correct, and as a customer it means it’s risky to buy if you care about the difference between refrigerated hot coffee and cold brew.

> It’s a market for lemons at this point. Unless you can see an expensive apparatus or observe them soaking the coffee, there’s no way to know if it’s correct Presumably the taste should tell you whether it's correct. Otherwise why care if they fake it?

If they "fake it" and it tastes better... then why are you going out of your way chasing some marketing term that tastes worse to you?

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#272

Post by eddd-ddde »

lamename wrote: post #32
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…

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…

I had zero idea that's what it was supposed to be. Cold brew reads to me as brew that is now cold.

Wouldn't it be a better term cold-brew or something like that?

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#273

Post by senkora »

base698 wrote: post #260
senkora wrote: post #42

Earlier quoted context omitted.

> 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?

Probably. To be honest I just find it convenient to use a French press as a cold brew maker and first-pass filter, because it is IMO easier to keep clean than a nut milk bag or coffee sock.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#274

Post by cafebee »

kibibyte wrote: post #250
NoGravitas wrote: post #123

Earlier quoted context omitted.

> I’m baffled that so many people who sell coffee for a living, think they know a lot about it, and act like coffee snobs, don’t seem to understand what cold brew even is. Light roasts came (back?) into style among coffee snobs a few years ago because it highlights the difference between different sources/regions/whatever. Ever since then, the former best coffee shop in my town has been exclusively producing sour, ve…

Light roasts are great! But there are just a lot of straight-up bad renditions of them, as a result of lack of adequate training on either roasting or brewing, to the consternation of many of those coffee snobs. Unfortunately, this just happens when shops follow trends. Roasting well in general is already quite challenging and is a lot more than just arriving at a certain bean color or temperature. Vegetal flavors ar…

What are the variables that a roaster can tweak? Temperature, time, and lots of others I assume? Which variable can produce vegetal flavors? I’d never thought much about roasting but now I’m curious!

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#275

Post by nubinetwork »

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…

I just pour coffee grinds into a recycled pop bottle... no need to get fancy with a French press.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#276

Post by bobthepanda »

dahart wrote: post #256
kjkjadksj wrote: post #197

Earlier quoted context omitted.

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 disc…

I suppose this makes sense? Baking soda’s main flavor profile is bitter, but coffee is already bitter so I suppose it isn’t going to make things worse. (Compare this to its use in baking, where you have to be careful not to use too much so the bitterness doesn’t ruin the baked good.)

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#277

Post by _akhe »

blincoln wrote: post #20

I'm disappointed that their test didn't include a comparison to traditional drip coffee made using the same beans, then chilled to match the temperature of the cold brew. I haven't looked into ultrasonic cavitation in years, but since it can produce enough heat and light to make some people wonder if it was a form of nuclear fusion back in the early 2000s, I feel like maybe it's affecting the flavour of the coffee at…

Interesting, microwaving with sound

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#278

Post by everettp »

csmpltn wrote: post #53
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 an extreme form of coffee hipsterism. “Cold brew, but steamed please”. Brother, this is starting to get ridiculous.

Would you say that a discussion about GPU densities was an "extreme form of processing hipsterism"? Unless your contention is that there is no observable difference between the types of drinks described by OP, this comment is an embarrassing ad hominem and has no place here

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#279

Post by croo »

ChrisMarshallNY wrote: post #240
solardev wrote: post #225

Earlier quoted context omitted.

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'…

Friend of mine, with money , has a coffee machine, by a company I’d never heard of, called “Jura”[0]. I’d not heard of it, because it’s not for plebes, like me. Grinds and brews a perfect cuppa in about a minute. I used to have a toddy maker, where you dumped a whole pound of ground coffee into a bucket of water, let it sit overnight, in the fridge, then you drained through a filter. The resulting thick liquid was li…

We have a Jura machine at my workplace since the beginning of time. It brews coffee as good as good the bean you use. After a month it asks for a cleaning cycle which is arcane magic, but other than that it just works and creates its daily 50-100 coffee as usual. I can recommend it, it just works.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#280

Post by nottorp »

Why 3 minutes? Fancy ways of brewing coffee bring more value via their ritualistic part than via the final product. Same for smoking a pipe, it's the filling up and cleaning that matters.

If you want speed, get a fully automatic machine. Ideally with a timer so your coffee is ready when you wake up.

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