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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

#181

Post by Spivak »

samcheng wrote: post #49
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.

I think this is called "Kyoto-style slow drip" coffee. I agree with you that the contraption should be in plain view of the customers! I remember being really interested in a cup of Kyoto-style one day, only to be told to make a reservation and come back tomorrow... it was worth the wait.

It seems to be a niche taste among my friends, yes it's sour and bitter that's why I like it!

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#182

Post by sushid »

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.

I'm a coffee snob and I can respect your preferences but have you considered non-coffee alternatives? Japanese and Chinese tea culture can be fun to delve into and tea would probably be easier on your stomach.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#184

Post by Bluecobra »

elevatedastalt wrote: post #164
fwip wrote: post #162

Earlier quoted context omitted.

Speculation: Cold brew takes more refrigerator space, which is relatively inflexible. Since it brews overnight, you have to put aside enough fridge space for all the cold brew you expect to sell that day. Contrast with regular coffee, which you make largely on-demand, with only the coffee beans to store overnight, on a shelf. So raising the price might be the sensible thing to do, to discourage purchases and/or pay f…

That's a good point. From what I understand, cold brew can be made at room temperature too. So it will need storage but not cold storage. But it's possible I don't have the full picture.

I have found no difference in just using cold water and having it sit on my counter overnight vs. keeping in the fridge. It is nice to still refrigerate it to use less ice or no ice though. In a retail setting, I would think customers would demand a cold product (I would). The Starbucks near me serves Nitro Cold Brew and for some reason it's always warm/room temp, and they purposely do not put any ice in it. Other locations seem to not have this issue so maybe it's broken equipment or training.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#186

Post by stephenhuey »

Bluecobra wrote: post #184
elevatedastalt wrote: post #164

Earlier quoted context omitted.

That's a good point. From what I understand, cold brew can be made at room temperature too. So it will need storage but not cold storage. But it's possible I don't have the full picture.

I have found no difference in just using cold water and having it sit on my counter overnight vs. keeping in the fridge. It is nice to still refrigerate it to use less ice or no ice though. In a retail setting, I would think customers would demand a cold product (I would). The Starbucks near me serves Nitro Cold Brew and for some reason it's always warm/room temp, and they purposely do not put any ice in it. Other lo…

Cold brew coffee is by definition not brewed with hot water the way most coffee is (in other words, room temperature is within the range of "cold" when talking about brewing with "cold" water). So, it's not necessary for it to be served cold to enjoy the benefits of the cold brew method--sometimes I like it chilled, but I also enjoy the taste at room temperature or warmer.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#187

Post by dhritzkiv »

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…

One thing I'll mention is that cold brew doesn't need to be put in the fridge to "brew". It can be left out on the counter at room temperature. As a result, this takes the brew time from 24 hours to about 12 hours.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#188

Post by dahart »

sushid wrote: post #182
dahart wrote: post #76

Earlier quoted context omitted.

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.

I'm a coffee snob and I can respect your preferences but have you considered non-coffee alternatives? Japanese and Chinese tea culture can be fun to delve into and tea would probably be easier on your stomach.

I definitely have considered alternatives, and do drink tea, more now than before, in part because of my negative experience experiences trying to get hot coffee that was cold brewed. Finding the fake cold brew many places really scares me off cold brew more than baristas who don’t want to heat the coffee. Single shot americano is another alternative with a bit lower acidity, I believe, and even with that I often get mild push-back from baristas… “you sure?? We pull two shots anyway…”

The main problem is that I love the flavor of coffee, and I feel especially jealous on a Saturday morning when I can smell it but can’t drink it. Secondary problem is adjusting to a consistent caffeine level without getting headaches.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#189

Post by i_am_jl »

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

Plunging pushes your coffee through the metal filter. Pushing harder pushes the coffee through the filter with a higher pressure. Higher pressure pushes particles past the filter more easily than lower pressure. Coffee particulate has a tendency to make coffee more bitter.

Anything that gets more small particles past your filter will add to your coffee's bitterness. This can happen when using a ground coffee that has a lot of fine particles, or if you agitate when you pour/plunge.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#190

Post by an_aparallel »

NoGravitas wrote: post #123
dahart wrote: 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…

> 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…

i live in Sydney - not far from UNSW :P Campos coffee are phenomenal roaster imo. There's no hype around these light roasts - i would never cold brew them though - i've tried - and it's an incredibly inefficient form of brewing. But light roast itself is a phenomenal thing :)
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