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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

#191

Post by mmanfrin »

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…

> I was laughed at in one hipster joint for asking for a steamed or warmed cold-brew

Not to discount the rest of your comment but it's a mild irony here for you to add the 'hipster' qualifier to a coffee place when you ask for steamed cold brew

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#192

Post by dahart »

fuzzzerd wrote: post #172
D13Fd wrote: post #109

Earlier quoted context omitted.

I drink only cold brew normally, and I've noticed this as well. It's 50/50 whether you will get actually cold brew at any given coffee shop or just iced hot-brew coffee, which tastes different and has much less caffeine. Cold brew needs a new name or it will likely fade away over time.

There's nothing wrong with the name cold brew. It describes the difference from "standard" coffee. It is the charlatans selling warm brew over ice that devalue it. As someone that greatly prefers coffee brewed cold and served on ice, I hope it doesn't fade away, because without it I have a lot less reason to get coffee out as opposed to at home.

There shouldn’t be a problem with the name, but my experience tells me that people don’t comprehend it the majority of the time, and assume incorrectly that cold brewed must be served cold. This mentality is even here in this thread in a few places. It does seem like some other word than “cold” might help avoid leading people into an erroneous conclusion.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#193

Post by romafirst3 »

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…

All coffees tend to be in the same ph range regardless of brewing technique.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#194

Post by askvictor »

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]

Cafes often charge more for niche items, mainly because they can. There's also the workflow of the barista to consider - leaving the espresso machine to get ice from the freezer disrupts the flow of constantly pumping out lattes.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#195

Post by janalsncm »

deadlydose wrote: post #118
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.

Risky to buy? It's not real estate it's a cup of coffee. And if you're worried about people faking it, just buy a $2 mason jar and make some in the fridge while you sleep. I don't get the fascination with paying exorbitant prices and constantly complaining when it's next to zero effort to make it at home, cold or hot. And the best part is you get to choose where your beans come from, you don't have to worry about the…

Yes, risky to buy. In the same way a slot machine has an expected value of 80-99% payout it’s still a bad use of money even if you only put in $5.

If you object to the word “risky” I used it in the sense of “uncertain you will get the value you expected”. Perhaps there’s a better word.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#196

Post by askvictor »

thsksbd wrote: post #77

I'm guessing few on this board have heard an uktrasonicator in action. I just showed to article to my mate, and he enthusiastically said we'll brew some... as soon as we leave the lab to break for lunch

> heard an uktrasonicator

Is this a joke?

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#197

Post by kjkjadksj »

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…

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?

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#198

Post by thrixton »

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.

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

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#199

Post by elevatedastalt »

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 is so much more caffeinated that I've seen most shops add tons of ice to create enough drinkable volume without giving you enough caffeine to knock a horse down.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#200

Post by kjkjadksj »

bananskalhalk wrote: post #55
bobthepanda wrote: post #50

Earlier quoted context omitted.

To be fair all you need to actually make cold brew is a pitcher and a cheesecloth or some other filter. The absence of an apparatus does not make it fake.

Chilling warm brewed coffee is definitely faking it. And I presume all places selling "cold brew" is faking it so this guy is losing money by not showing off doing real cold brew with his apparatus.

The way I've seen it done is with one of those massive plastic commercial kitchen lidded containers, and a softball sized teabag of coffee sold by the restaurant supply company specifically for cold brewing like this. Then they put it in the walk in for a while to steep and sell it after a certain number of hours.
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