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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

#211

Post by mianos »

"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, people were talking about it years ago on the forums on this stuff.

Maybe they don't have internet over there at UNSW. They can come over and borrow mine for a bit of a search. I am just a few ks away. Or go to that internet cafe in Kensington in the next block.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#212

Post by sq_ »

panopticon wrote: post #137
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…

This is mainly what got me into roasting my own coffee. It was becoming a pain to find high quality dark roasts as all of the boutique roasters turned their efforts to light roasts.

I hadn't thought of that as part of why finding good dark roasts has been hard for me. I've been annoyed at light roasts for a long time because I tend to find them acidic to the point that they're not enjoyable. I appreciate the bitterness and toastiness of a good dark roast, but finding good ones has been few and far between in my experience.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#213

Post by shirro »

Wake up yourself and all the dogs in the neighborhood at the same time. I want one.

I went through the obligatory Australian fascination with espresso and am well over it. It is a load of fetishistic bs and scalding hot coffee is disgusting. I buy bottles of cold brew from a local roaster and avoid the hassle.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#214

Post by papertokyo »

dahart wrote: post #151
shawabawa3 wrote: post #108

Earlier quoted context omitted.

But hot cold brew is weird, as you've just been complaining about people not doing it or finding it weird If hot cold brew was common you wouldn't pay extra for it

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 paying more for iced coffees compared to hot ones too:

https://www.broadsheet.com.au/national/food-and-drink/articl...

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#215

Post by lytfyre »

this_steve_j wrote: post #132
opwieurposiu wrote: post #34

Earlier quoted context omitted.

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.

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 play with the style without investing the money and space. Still want one of those towers if I ever see them cheap though.

[1] https://puckpuck.me/ - no connection, just a customer.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#216

Post by lytfyre »

artimaeis wrote: post #124
dahart wrote: post #93

Earlier quoted context omitted.

It’s not an unusual order, hot coffee is sold millions of times per day, and steaming comes with many coffee drinks, it’s par for the course with espresso drinks. Roasting a salad is weird, hot coffee is not, so your example is straw man. The “cold” in cold brew is not referring to serving temperature, that’s your own misunderstanding, so I find the suggestion that hot cold brew is weird to be pretty funny. As has be…

Former barista, it _is_ an unusual order from the perspective behind the bar. Unusual in that I never have heard of someone ordering a warmed cold brew. I'm not certain how I'd warm it up. I suppose it could be poured into a clean frothing pitcher and steamed directly, I'd somewhat worry that might dilute the flavor of the coffee. I don't reckon someone's going to want me to microwave their cold brew, but it certainl…

Coffee nerd, I like to play with this stuff. Steaming cold brew (flash or regular) will give a very smooth frothy texture - almost nitro like foam. You can serve them over ice to get them back to cold, or serve warm.

Tasty if you use good coffee, and pretty unique honestly - "steamed iced americano" or "aerocano" are the two names I've heard if you want other people's reports on them.

You're right that it's very different from the experience of microwaved cold brew, and a customers response can be all over the place depending on what they're expecting.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#218

Post by panopticon »

thrixton wrote: post #198
panopticon wrote: post #137

Earlier quoted context omitted.

This is mainly what got me into roasting my own coffee. It was becoming a pain to find high quality dark roasts as all of the boutique roasters turned their efforts to light roasts.

How did you go about roasting your own if you don’t mind me asking.

It was a journey! My wife got me a roaster for Christmas several years ago, and I had absolutely no idea how to use it. After tons of reading, YouTube, and trial-and-error I eventually got the hang of it. I still use the same roaster she bought me, but I upgraded to a double-walled chamber to make winter roasting more consistent and temperature probes [1] to record the roast process with Artisan [2]. Since collecting data is fun and makes it easier to get consistent results.

I don't roast beans for cold brew anymore since I drink way too much and it was becoming a chore, but I still roast ~8oz every two weeks for pour overs.

If you're interested there are a lot of great resources online. Sweet Maria's [3] has been a constant go-to for knowledge, equipment, and green coffee beans. And of course, YouTube.

1: https://imgur.com/T0WW90R 2: https://artisan-scope.org/ 3: https://www.sweetmarias.com/

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#219

Post by lytfyre »

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.

Wouldn't knock it till you try it! The drink kinda had it's moment a couple years ago - "Aerocanos" or "Steamed Iced Americanos" are the names I've heard for the drink. Often made with the kind of post-brew chilled cold brew that OP was railing about. Cold coffee, steamed to frothy, then either pour over ice to re-chill or serve warm.

Wouldn't try to randomly talk a barista into making one, but if you see them on the menu at a shop or have an espresso machine, they're pretty neat.

Video on them: https://www.youtube.com/watch?v=tD_4hOg_SWU

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#220

Post by papertokyo »

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?

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