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Cold brew coffee in 3 minutes using acoustic cavitation

unsw.edu.au

261–270 of 361 posts

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#261

Earlier quoted context omitted.

Your ambivalence contributes little to the conversation.

Wait till you see my cookbook, "1-minute Meal Replacement Powders", the perfect complement to my self-help/self-sabotage title, "Better Living Through Lower Standards". YOLO, and no one gets it right on the first try anyway...

You may be interested in my philosophy on uptime: nine nines is hard, how about eight eights.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#262
post #40

Earlier quoted context omitted.

> brew temp and serving temp are orthogonal Yes!!! I’m biting my tongue a little on how infuriating the process has been to ask cafes for warmed cold brews, but you’re spot on and exactly right. 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. (Or, in a few cases in my sampling I’m certain it was w…

In my experience having worked in coffee shops, restaurants and bars, there is a considerable overlap between the people asking for something off-menu that nobody has ever asked for, and the people who will never be satisfied with their order. It might seem like a very simple ask, but I think many people working in those jobs have learned it can be expedient to just say “we can’t do that” and short circuit the intera…

I can understand that. I do feel like the reaction I’m sometimes getting is reflexive and not given any thought. My daughter worked at Starbucks for a while, and told me about crappy customers doing this all the time - ordering drinks with questionable modifications and then sending them back when it wasn’t as good as they hoped. Her initial reaction to my steamed cold brew story was that I’m asking for something unusual. For the record, I have never sent back a warmed cold-brew for any reason.

That said, part of what I’m blabbering on about is that I think cold-brew served hot should not be considered off-menu, I don’t think that’s entirely fair. Since cold brew served cold is an assumption in the first place, it seems like hot cold-brew is (or should be considered) just as on-menu as cold-served cold-brew. It’s fine that the assumption exists, I just don’t understand the pushback when I specify warm. I feel like calling a steamed cold-brew off-menu is exaggerating, considering that a) iced coffee exists; b) steaming espresso drinks is extremely common(!); c) many cafes that make espresso drinks essentially offer all combinations of brewing process, coffee, milks of various kinds, and flavorings. It’s so crazy to me to get shit for asking for a steamed cold-brew when something like a Caramel Ribbon Crunch Frappuccino with an Affogato shot and extra espresso exists and isn’t even considered weird or extreme. Maybe some cafes are pushing back against customers with Starbucks expectations, but they still offer a selection like espresso, cortado, mocha, latte, americano, flat white, blah blah blah. It’s like Mexican food, there is a name for every possible permutation of grounds, water, milk, sugar, and heat. Given that they have cold-brew, that they have a steamer, and that serving hot coffee and steaming things are both standard every-day every-order kinds of things, I simply can’t understand why I’d get pushback even if I am asking for something weird. I’m asking for something weird that is completely and trivially doable.

Anyway, you’re right. I know I’m peeing into the wind just a little. It is what it is, which is why it’s a waste of energy to fight it or complain about it. :P

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#263
post #151

Earlier quoted context omitted.

The biggest sticking point is not the heating of the coffee at all, it’s the widespread misunderstanding of the what the word cold means in the term “cold brew”. It is incorrectly assumed that brewed relatively cold (room temperature) means served ice cold. Somehow a lot of people can’t understand the verb brew has nothing to do with serving temperature. Does that make sense to you?

Although you are entirely correct in a technical sense, and it's common to serve hot brewed coffee cold, the opposite is so rarely desired that it will be considered 'weird' (in the sense of 'unusual') 9 out of 10 times. Every extra process involved in making a coffee is going to add complexity and time to the workflow, which many cafes will elect to charge extra for. There is some consternation in Australia about pa…

I know, I know. You’re right. But… even if it is weird, it is so easy! It’s not really the default assumption that’s frustrating, it’s when I get push-back for a request that is normal and default for other espresso drinks, something trivially doable, something every barista does dozens and dozens of times a day.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#264
post #66

Earlier quoted context omitted.

It's funny cuz Charbux has no problem pouring hot espresso into cold ice milk with caramel and cream on top. I think it's pretty clearly just "baristas" justifying not changing their process, which is fine if a bit lazy and argumentative. Many coffee people are totally interested in finding new ways to do stuff, but they have to have the mental space to do it.

Starbucks cold brew is actually not bad as far as cold brews go. It’s definitely not iced coffee.

They do serve both, and they're different. Close enough for me, so I get the iced coffee cause it costs less and I respond to incentives.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#265
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 love that! The context I didn’t put in my top comment but added elsewhere is that this old washed-out dev requires low acidity because regular coffee was causing inflammation in my throat. That’s really all I want, less acid in my coffee, not something fancy. Except that I don’t want it cold, I want it hot like I’ve always had it. Other than that, I’m like you, I’m also perfectly fine with a perfectly average mediocre cup of joe.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#266
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…

At my friends coffee shop they make cold brew with an elaborate laboratory glassware setup that drips ice-water through a filter. Looks pretty neat and sciencey. They got 4 of these devices running all the time in the back room. I was telling him all the other shops in town just fake it, he should put one of the devices out front so people can see his cold-brew is for real.

One that I'm aware of - Black Blood of the Earth - https://www.funraniumlabs.com/the-black-blood-of-the-earth/

> Fast forward 14 years. An acquaintance working and living in Japan went on holiday and discovered a bar with this exceptionally beautiful rig for the preparation of Viennese Triple Cold Extraction Coffee. Upon sampling this, he felt that, and I quote, “I could see colors that weren’t in the visible spectrum, and could vibrate through walls.” I looked at this I said to myself, “Hey, you’ve got enough virgin laboratory glassware lying around the house that you could probably build something like that.” Probably several somethings, actually, but that’s beside the point.

It has a picture of the original glassware in Japan and his first iteration in the kitchen. A sibling comment links to Yama glass ... which is out of Taiwan. The similarities might not be coincidence.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#267
post #265

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'…

I love that! The context I didn’t put in my top comment but added elsewhere is that this old washed-out dev requires low acidity because regular coffee was causing inflammation in my throat. That’s really all I want, less acid in my coffee, not something fancy. Except that I don’t want it cold, I want it hot like I’ve always had it. Other than that, I’m like you, I’m also perfectly fine with a perfectly average medio…

Small amounts of potassium bicarbonate can be used to neutralise the remaining acidity. This helps prevent bitterness, and should not harm other aspects of the taste, unlike sodium bicarbonate. Dissolve into cold water, mix throughly, then add coffee grounds and stir. If you intend to store it, complete absence of light and absence of O2 wild also help prevent bitterness.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#268

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…

I would buy a book of you talking about coffee.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#269

Earlier quoted context omitted.

No. These machines sound like robot hornets operating dental drills.

I thought ultra sonic was defined as being above the sonic range of humans. Genuine question: why would an ultrasonic noise generator create sound audible frequencies? Can it not provide enough power without doing so?

Ultrasonicators for the purpose of cavitation research are insanely powerful and non linear material response cause all sorts of vibrational modes to boom.

Its unpleasant.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#270

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'…

But how do you waste time in the morning if you’re not concocting some over complicated drink? I feel like my morning coffee is the one part of my day that I can control. You bet I’m gonna take my time and make it enjoyable.

I also like the "ritual" of brewing a coffee to help me wake up in the morning. And even then, it's less than 10 minutes total preparing a pour over, it probably takes less time than cleaning out a filter machine would.

And for people thinking you need some $$$ machine, even the most pretentious experts agree that pour over is about as good as that style of brewing can get (IE not something like espresso). A hand grinder and plastic v60 will get you to the point you're not limited by the equipment. The biggest expense is the beans themselves, and that's as much a taste thing as anything else.

But I guess like any hobby you there will be people selling you all kinds of things at any price people are willing to pay - maybe it makes it a bit easier, maybe a bit quicker, maybe it looks better on your counter. Maybe it gives you something a bit different and unusual. But none of it gives you better coffee.

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