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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

#281

Post by atoav »

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…

As someone who regularly makes cold brew during hot summers, the tale is that the acidity is lower — or at least of a different kind.

Hot brewed coffee starts to taste bad after a few hours if you let it go cold, cold brewed coffee tastes differently from the start, but won't develop that bad flavour even after a week in the fridge.

The key for a good cold brew is however that the bean/roast is of very good quality. And it is quite simple to make. The way I do it:

1. Grind coffee coarsly and put it in a glas jar that can be closed. The amount of coffee can be adjusted quite freely, but I'd go with one fourth/fifth of the volume of the jar. More bean = more concentrated coffee.

2. Add cold water and stir

3. Put in the fridge and stir at least once in the morning, once in the evening.

4. After ca. 24 hours you can run the whole thing through a coffee filter to extract the coffee. It is also possible to reuse the coffee-sludge once if you add some fresh beans.

That is not too complicated and worth a try. Please avoid pre-grind cheap coffee for this, It will taste like bullshit.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#283

Post by enobrev »

bobthepanda wrote: post #50
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.

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.

French press with cool water over 24 hours is simple and works well.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#284

Post by lostlogin »

Xerox9213 wrote: post #227
solardev wrote: post #225

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.

> But how do you waste time in the morning if you’re not concocting some over complicated drink?

Many relaxing things are part ritual. I like your thought process.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#285

Post by lostlogin »

kimixa wrote: post #270
Xerox9213 wrote: post #227

Earlier quoted context omitted.

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 gri…

> 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.

The Faema e61 Legend isn’t quicker or easier, but damn it is pretty.

And that makes the coffee better. It’s also an effective space heater.

https://www.faema.com/uk-en/product/E61-MONOFASE-ANNIVERSARI...

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#286

Post by lostlogin »

cafebee wrote: post #274
kibibyte wrote: post #250

Earlier quoted context omitted.

Light roasts are great! But there are just a lot of straight-up bad renditions of them, as a result of lack of adequate training on either roasting or brewing, to the consternation of many of those coffee snobs. Unfortunately, this just happens when shops follow trends. Roasting well in general is already quite challenging and is a lot more than just arriving at a certain bean color or temperature. Vegetal flavors ar…

What are the variables that a roaster can tweak? Temperature, time, and lots of others I assume? Which variable can produce vegetal flavors? I’d never thought much about roasting but now I’m curious!

I roast my own with a heat gun.

5 mins or under and it’s scorched, 10 mins or over and it’s baked. I want in the middle.

Too dark and oily and it’s not great. Too light and I miss the bitterness and it tastes weak. I need to stir it a lot or the roast is uneven. I spray water on it at the end to arrest the roasting.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#287

Post by omnimus »

dahart wrote: post #204
mmanfrin wrote: post #191

Earlier quoted context omitted.

> 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

Why’s that? What’s ironic? Do you feel like that’s a fair gotcha? Do you know why I asked for a heated cold brew? I’m asking for cold brew because my esophagus gets inflamed with higher acidity coffee. I used hipster not as pejorative, but to indicate this is a cafe that claims to, and should, know the difference between cold brewed and hot brewed coffee. In fact, I’m certain the owner does know the difference and th…

Sounds like you are the snarky hipster. The barista didnt know this process and didnt have it on menu. In their eyes its just strange request asking for trouble.

I think of myself as very knowledgable barista and this is first time i am hearing this. I checked usual resources like James Hoffman and nobody is even mentioning heated cold brew. So its very niche and sounds more like something from camping.

I believe you that health wise its for some people better. But cold brew overall is not that popular with coffee fans because the coffee is underexttacted - it tastes ok but you will get more flavours using hot water. Its kinda waste to use high quality coffee on cold brew. But thats where i personally like cold brew - with lower quality coffee it can taste better than hot extraction.

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#289

Post by TrueSlacker0 »

bobthepanda wrote: post #50
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.

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.

100% agree. This is exactly what we do at our brewery and it comes out great. A simple fermenter with a pour spigot works wonderfully (we use this one because we already had it [1]). Soak the ground beans for 12-24 hours in a mesh bag in the cooler, remove the bag and drink on it all week.. or till it's gone.

[1] https://www.ssbrewtech.com/products/brewbucket

Re: Cold brew coffee in 3 minutes using acoustic cavitation

#290

Post by jorvi »

Xerox9213 wrote: post #227
solardev wrote: post #225

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'd say in life you generally want to stick to 20/80 80/20.

Spend 20% in effort and/or currency to get 80% of the optimal result. Spending the other 80% to get another 20% gain is rarely worth it.

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