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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

#331

Post by anonuser1234 »

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'…

You've got a perdy writing style

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#332

Post by insane_dreamer »

currency wrote: post #311
benjijay wrote: post #307

Earlier quoted context omitted.

I was recently discussing this with a colleague and we settled on calling it quality creep - as you become used to better things, the stuff that was previously acceptable becomes unbearable. e.g. I used to drink any old instand coffee, then I found Douwe Egberts and strongly preferred that for a few years, then I started making pour-overs with pre ground coffee in a v60, then I found a better grind/roast/etc of the b…

Making espresso with my semi-auto Breville Infuser is almost exactly as much fuss as a pour-over: - Turn it on to heat up - Grind the beans - Weigh the grounds - Fill, tamp, and attach the portafilter - Start the infusion - Remove and dump the grounds - Clean the portafilter It's a $600 electronic device, not a simple funnel and filter, but it's not a fussy process.

You still weigh the grounds? The difference with eyeballing it is probably too negligible to be noticed.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#333

Post by LargoLasskhyfv »

waldothedog wrote: post #237
LargoLasskhyfv wrote: post #115

Earlier quoted context omitted.

Funny. Exactly that stuff is the only reason I've ever entered a Starbucks. Venti! But TBH one can do that with better coffee, caramel sirup, some crushed ice from the fridge, and even spray cream out of a can for much less money, just not 'on-demand' and anywhere/anytime. Also, too much (spray) cream and caramel in Venti amounts can't be that good for your body.

Why not trenta?

Burst prevention.

edit: Also price, the last time I had that it was about 6EUR for Venti, while that even bigger thing would have been just slightly under 10EUR.

Which I think of as insane, considering the not that special ingredients. That was years ago, long before COVID. Didn't go there afterwards, neither in .de, .eur, or the .us. Don't want to support that franchise chain mindfuckery.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#334

Post by dahart »

romafirst3 wrote: post #193
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.

This contradicts the common claims about cold brew. Do you have any references on it? When I google it now, the first answer I get says hot brewed gives a pH around 4.8 and cold brewed around 5.1, which if true is a 2x difference in acids. My home tests with pH strips show drip and pour overs to be a bit more acidic than a very fast aeropress.

There are low acidity beans, and as I just found out additives to counteract acidity that won’t compromise the flavor, such as baking soda. I guess I might head more in that direction and stop worrying about cold brewing.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#335

Post by BrandoElFollito »

solardev wrote: post #328
BrandoElFollito wrote: post #304

Earlier quoted context omitted.

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.

Oh, absolutely. I wanted a zero-maintenance system because I know myself and it would not end well.

My wife was considering a mid-range+ coffee maker where you would have two bean containers and make combinations. It cost a fortune (on my personal scale) and I told her that she lost her mind. And then did an Excel sheet where I realized that the two lines meet at 12 or 15 months...

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#336

Post by anon84873628 »

surfingdino wrote: post #65

James Hoffman's video on the subject incoming in 3... 2... 1... can't wait :-)

He's already spoken many times about cold brew. including his preference for iced filter as opposed to true cold brew. which may have contributed to the exasperation expressed in the current top comment.

Maybe the Coffee Lit Review podcast will cover this, but honestly it's not that interesting. Cavitation has already been done many times.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#337

Post by YetAnotherNick »

eternauta3k wrote: post #170
YetAnotherNick wrote: post #75

Earlier quoted context omitted.

Also, in my experience heating the coffee in microwave increase perceived acidity even more. Which kind of make sense with this explaination as there could be pockets of superheated water when it is microwaved.

Could you try giving it a good stir right before putting it in the microwave?

Just curious, why do you think that would help?

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#338

Post by i_am_jl »

hammock wrote: post #201
i_am_jl wrote: post #189

Earlier quoted context omitted.

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…

I don’t know anyone who’s jumping up and down on the plunger or doing anything more than pressing it slowly. Have to imagine the coarseness/evenness of your grind is a 10x bigger factor in that regard

>I don’t know anyone who’s jumping up and down on the plunger or doing anything more than pressing it slowly.

Also my reaction the first time someone tried to tell me to plunge slower.

>Have to imagine the coarseness/evenness of your grind is a 10x bigger factor in that regard

100%. Plunge speed makes a minor difference at most, and only then when you have a suitably coarse and even grind.

If you want to play with the concept I think the best way is to prep a press, but instead of plunging the filter into the coffee before pouring, press it only to the top of the liquid and pour, allowing gravity to pull coffee through the filter. Pour a small cup like this, then press the rest of the way and pour another cup.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#339

Post by SAI_Peregrinus »

Terr_ wrote: post #154
lamename wrote: post #32

Earlier quoted context omitted.

Thank you for saying this. When cold brew first came out, it was promoted as a brewing process that resulted in smoother (I'm guessing lower acidity) tasting coffee. Heating it up seemed natural, and its use in iced coffee seemed simply opportunistic. (In my experience at least). Then it quickly caught on as a novelty, with nitro et al, and when I tell people I drink cold brew warmed I get looks of confusion or turne…

> But brew temp and serving temp are orthogonal. And if anyone doesn't believe this, challenge them to find a truly "iced" coffee. :p

Coffee popsicles are easy to make. Or put coffee in an ice cube tray, freeze it, & use it instead of water ice when making a regular "iced" coffee. No dilution as the ice melts!

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#340

Post by bigDinosaur »

Spivak wrote: post #179
dmix wrote: post #156

Earlier quoted context omitted.

You're saying Europeans are less smug than Americans?

It's less about smugness and more that customer-service people are expected to behave like AI and always have an answer whether it's correct or not. I hope at some point we can drop the facade and "I don't know man, I just run the till. Do you want coffee or not?" becomes an acceptable response.

I can't speak for the US but people absolutely do not act like this in Europe (and Europe has some of the most arrogant self-assured service workers on the planet depending on the country - I won't name names but you can probably guess which country has the most extreme and limiting arrogance around what should or should not be done with coffee).
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