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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

#321

Post by anon84873628 »

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…

And yet if you asked for the "aerocano" as seen on YouTube, they would probably be happy to oblige.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#322

Post by manishsharan »

eichin wrote: post #142

Ooh an excuse to upgrade some homelab equipment :-) (My preferred "weird" coffee is sous-vide: 125g/liter, 2h @ 150f - so you don't leave as much flavor "on the table", but by not getting near boiling you leave more of the bitter compounds behind. Refrigerated but served iced or warmed with boiling water, to taste.)

I would like to try this. Are you using ice cubes to vacuum seal or do you have some fancy gadget that I must have !

We need Lance Hendricks or James Hoffman to do experiments and determine the best temperature.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#323

Post by anon84873628 »

majormajor wrote: post #145
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.

Unless I'm a visiting tourist I'm likely to go back to a good coffee shop many times. Being surprised my cold brew isn't cold brew - both the caffeine content and taste are tells IMO - for one visit isn't life or death here. I just don't get it again.

Caffeine content in the cup is not a good metric. It is one of the most easily extracted compounds and is roughly equivalent across brew types. The beans themselves are a bigger variable in this regard. Even if you are using a roaster's signature blend, the bean composition of that is going to change month to month and year to year. Even beans from the same physical trees will have varying caffeine content depending on agronomic factors.

In the same cafe on the same day, the reason different drinks have noticeably different caffeine content comes down to the different doses and concentrations they end up using. E.g. 20g coffee would normally produce either a 40mL espresso or 12oz drip. So putting that 40mL espresso in a 5oz cappuccino is much more concentrated than a 8oz filter.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#324

Post by area_man »

solardev wrote: post #243
ChrisMarshallNY wrote: post #240

Earlier quoted context omitted.

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…

That's actually the brand I have, and I'm as plebe-y as they come! I even have a mining pick in my garage that I use for manual labor. I'm nothing like the guy in the photo, more like the guy who makes the coffee for the guy who makes HIS coffee. You can get Juras for pretty cheap if you go bargain hunting. There are also other similar but cheaper brands. As a category, they're called "superautomatic espresso machine…

It need not be mediocre. I have a Jura J5 which has, as of this morning, made 18,901 espressos. A few years back, I bought the tool to open it and recalibrated the conical grinder. There are now videos that can walk you through this process.

The mediocrity disappeared. It produces a fantastic brew close to the quality of the shop where I buy the beans.

Before attempting all this, I ran an experiment. I had my shop grind the coffee one notch back from where they grind for their in-house espresso. Then I put that into the by-pass chute and brewed it. This confirmed to me that machine’s grinder was not getting fine enough.

If you grind truly as fine as you would for an espresso machine, you may get a very slightly better brew, but it will come with a 5% chance of clogging the machine and wasting the ground coffee. Best not to fly too close to the sun.

A friend who knows a few things about coffee stopped by not too long after I did this conversion and asked if I had bought new beans, because “this shit is top notch”. It was a revealing experiment about the importance of the grind.

It’s a fascinating machine to take apart. We’ve had it for 15 years and I’m optimistic it will just keep going. At this point my goal it see when the espresso counter will roll over back to zero.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#325

Post by 19f191ty »

spython wrote: post #173

Or you could use a (quite affordable) ultrasonic machine designed for gentle cleaning of jewelry, dentures, glasses.. I've used one to extract fragrance from biological material for an artistic project[0], and it worked really well. Instead of having to wait for a few weeks for a tincture to finish, you put the same tincture (alcohol and material you want to extract fragrance from) into a plastic bag for just 15 minu…

This is what I was thinking. If it's mostly fine scale mechanical agitation one is after then there are many ways to do it. An ultrasonic cleaning machine being the closest in spirit to their approach.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#326

Post by joshfee »

elevatedastalt wrote: post #139
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…

The emperor really has no clothes when it comes to food fads. And pricing is a completely orthogonal and obtuse concept too. Cold brew is putatively low effort and low cost. Just let coffee grounds soak in water overnight and you have cold brew. But it's often charged more than regular coffee or espresso-based drinks, which a) use more expensive equipment b) need more skilled operation c) more material [milk etc]

The mistake here is thinking that cost and price are related beyond determining what the final margin is.

The consumer decides the price that is acceptable for the good - the cost of that good being higher or lower just changes the viability of the product and the bottom line from selling it. So it makes tons of sense that given two similar products that consumers will pay a similar price for that companies would prefer to sell the one that costs them less.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#327

Post by qwerty456127 »

robocop_legacy wrote: post #316
qwerty456127 wrote: post #282

You can also make reasonable (not excellent, not terrible) brandy this way by putting vodka and oak wood shavings of a suitable kind into an ultrasound machine.

I think it would be similar to an aged whiskey, perhaps. Brandy is distilled from wine. Bourbon is primarily from a corn mash, so maybe with the right vodka.

Yes, I think you're right.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#328

Post by solardev »

BrandoElFollito wrote: post #304
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'…

This is more or less what I get as well with my Nespresso machine (it costs 1€, you have to buy x€ of coffee every month which is OK for me). The average cost of a coffee is 0.4€. The great thing is that it has zero maintenance and zero cleaning. I should probably do some de-limestoning (yes, there is a correct word for that that escapes me now) but I just avoid looking too closely.

Totally. I think the Nespressos actually make better coffee. I just wanted something that produced less plastic waste. The only waste outputs of this machine are spent grounds and water (well, and heat). And I can put in any whole beans I like (we just get ours from Trader Joe's), not limited to the Nescafe ecosystem.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#329

Post by solardev »

justin66 wrote: post #314
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'…

> What more could an old, washed-out dev ask for? From the sound of things, Soylent. https://soylent.com/

Heh, we actually order many boxes of a similar thing (Huel) every month. It's about half of our monthly food intake (by calories).

As a kid I used to dream about being able to photosynthesize. I'd love to never have to worry about food or beverage intakes again.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#330

Post by insane_dreamer »

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'…

Our Breville makes good espresso for 1/4 of the price of that machine. (We have a separate grinder, so it's a semi-manual process to grind each day.) So much depends on the quality of the beans you buy and how you store them.
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