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Cold-brewing of coffee by picosecond-pulsed laser extraction
- hasperdi 4y agoI drink cold brew coffee. Normally I leave the coffee to brew for 24 hours. I’m considering of buying ultrasonic cleaner for brewing my coffee. I wonder if that’s going to work. Watching YouTube videos on smoking / flavouring liquor using these cleaners gave me the idea.
- peddling-brink 4y agoThat doesn’t sound food grade. Is there a method to line the cleaner basin with something food grade?
- hasperdi 4y agoThey put the drink in a mason jar https://youtu.be/YlQT4ptwLKs?t=15h34m https://youtu.be/YlQT4ptwLKs?t=15h34m And that jar goes in the cleaner
- daniel_reetz 4y agoThis also works for cleaning items in solvents and flammable liquid. Put a secondary reservoir inside the ultrasonic tank.
- zoltar 4y agoJames Hoffmann tried it here: https://www.youtube.com/watch?v=2meeYcxXoVs https://www.youtube.com/watch?v=2meeYcxXoVs
- andreareina 4y agoN.B. not cold brewed coffee
- tmikaeld 4y agoQueue a Kickstarter to buy an expensive but extremely attractive coffe-laser brewer, expected to arrive July 2023, already in pre-production with "not"-rendered images.
- leobg 4y agoSo how does that work? How does the laser help extraction? Is it like they’re just heating small bits of grounds over at a time for short durations only, as opposed to heating the whole heat and all the water at once? So still heat extraction?
- bertolomeos 4y agoA German article [1] summarizes the technique as using the laser to reduce the size of coffee grains without generating enough heat to break apart the aromatic compounds. Based on this explanation, I would say this method is not equivalent to heat extraction. https://www.scinexx.de/news/technik/skurril-cold-brew-per-laserpuls/ https://www.scinexx.de/news/technik/skurril-cold-brew-per-la...
- tmitchel2 4y agoHard to heat something transparent with light radiation, whereas I guess the powder can absorb it
- tmitchel2 4y agoSo yes still heating? Ah no I see the alternate explanation now
- denton-scratch 4y agoI've never drunk cold-brewed coffee. According to the article, cold-brew has "less acidity and bitterness". I happen to like coffee with fruit and citrus tones. I'm not a coffee bore, but I have understood that coffee bores refer to that fruitiness as "acidity". Does that mean that cold-brew would be less fruity? The authors take "acidity" to mean "pH", which is obviously easier to measure than "fruitiness", but I wouldn't describe the taste of e.g. spirit vinegar as "fruity". Supplementary question: why's it got to be a picosecond laser? They say that a nanosecond laser's pulses are too long, and cause heating. How hot does it have to get for that to be a problem? Can't you just cool the brewing vessel? Supplementary supplementary: can apparatus for doing this be built at home? How much ps-laser power needs to be delivered to the brew? At what wavelength? You can get handheld picosecond lasers for things like mole and tattoo removal, for under $100; would one of those do the trick?
- tapland 4y agoA lot of people say cold brew is fruitier. I'd give it a shot if I were you
- thejosh 4y agoIt depends on the cold brew, they all have different tastes.
- GordonS 4y agoIt really depends what coffee beans you are starting with, and the roast, just as it does with "regular", hot brewed coffee. I also like lighter-roasted fruity beans, and cold-brewed tends to reduce the "sourness". IMO cold brew really shines for non-fruity beans though, greatly reducing the bitterness. You should try it!
- denton-scratch 4y agoHmmm. I've been alternating Ethiopian Harrar with Kenya AA. I buy them ready-roasted - I don't know how to characterise the roast other than "medium" (the beans don't glisten with oil). I alternate specifically to catch the fruity aroma, which seems to my jaded old palate to fade after a week of the same bean.
- pushedx 4y agoI’m constantly baffled by cold brew coffee seeming like a mysterious and arduously-obtained concoction. Stick ground coffee in some filter bags and put it in some cold water in the fridge. Come back the next day and drink it. Leave it in there however long you want.
- ct0 4y agoCold brew should be brewed at room temperature, then stored in the fridge. It's considered cold because it's not brewed at 190*f.
- dangerlibrary 4y agoWhat are the consequences of brewing in the fridge vs. at room temperature?
- goldenkey 4y agoFungus and mold will likely appear if you brew anything with water at room temperature. Use the fridge - trust my experience. It may take a bit longer to brew at colder temperatures, due to decreased convection of the liquid, but it will taste much better, as it prevents bacterial and fungal growth.
- hericium 4y agoI believe fungi aren't too fond of caffeine.
- goldenkey 4y agoPerhaps, but I've cold brewed black tea enough times with moldy results to forewarn y'all.
- yunohn 4y agoMold (a fungus) has grown in my refrigerated cold brew enough times for this to be false. More here - https://kitchenappliancehq.com/can-cold-brew-coffee-mold/ https://kitchenappliancehq.com/can-cold-brew-coffee-mold/
- ajaimk 4y agoJust take my money!!!
- yawgmoth 4y agoI had trouble understanding the method - were there 2 lasers? "Nd-YAG-laser centered at 532 nm" and "A ps-laser (Edgewave) with a pulse duration of 10 ps, a repetition rate of 80 kHz, and pulse energy of 125 µJ"? Perhaps they are one and the same? Where can I find cheap lasers to try something like this?
- rsfern 4y agoI think the second sentence is just describing the manufacturer and the pulse configuration of the one Nd-YAG laser. Sometimes a second laser is used to pump the output laser in pulse laser systems, but that’s an implementation detail and I’m not sure about the specific system used here. You might be able to find a laser system to hack around with (they are used for tattoo removal). Probably not cheap. Make sure to take laser safety super seriously if you work with lasers https://ors.od.nih.gov/sr/dohs/safety/laboratory/Pages/laser_safety.aspx https://ors.od.nih.gov/sr/dohs/safety/laboratory/Pages/laser...
- Alex3917 4y agoSimilar to this, anyone here tried Osma and have thoughts?: https://drinkosma.com/ https://drinkosma.com/ (Extracted via acoustic cavitation.)
- avidphantasm 4y agoThis has inspired me to try running room temperature water through my Flair espresso maker to see what happens. It’s worth a shot!
- avidphantasm 4y agoJust tried it with some medium roast beans. I ground it a little finer than normal. The water shot through very quickly, like 1-2 seconds. I poured the results back into the brewing vessel and pressed it through again. This time it went through slower (likely because the coffee was saturated by this point) and even made a little crema. It’s not quite cold brew, but reminiscent the of cold brew. Definitely worth more experiments.
- sgc 4y agoTry pre-infusion. Press slowly until you get one or two drops through, wait 30 seconds or so for the grounds to absorb water, then finish the single pass as slow as you can reasonably do so.
- anon84873628 4y agoCheck out the Lance Hedrick review of this device on YouTube.
- tiborsaas 4y agoIs this the sort of thing that bored engineers invent? :)
- hericium 4y ago> Cold-brewed coffee is attributed to health benefits, fewer acids, and bitter substances. IMO statements like this have no place in scientific papers. Attributed by whom? Less bitter than which method of hot brewing? Fewer acids than what - coffee made with all hot brew methods including AeroPress?
- aj7 4y agoUtter nonsense. And everybody got paid for doing this. An industrial grade picosecond laser is $150k. It has so little throughput that it must be used only for very high value products. In fairness, did anyone notice a finding in this paper that might lead to a cost-effective process by a different technology? Was this the April 1 issue?
- findalex 4y agoThis is how general research works. For better or worse.
- amelius 4y agoAlso, they didn't scientifically evaluate the taste of the coffee using a test-panel? Disappointed.
- xbar 4y agoUtter nonsense is an exaggeration. Is this good, important, or foundational science? I do not think so, but there may actually be practical applications for rapid production of high-caffeine cold brew coffee. Do you find the method fraudulent or were the outcomes poorly selected or measured?
- ajot 4y agoMaybe not even coffee. Maybe this can extrapolate to other liquid extraction methods from ground solids, if it can help reduce heating, or time for processes that are nowadays done at room temperature. Think minerals, beer, soy-sauce; economies of scale could afford this type of technology.
- aj7 4y agoI think you are right that I was immoderate.
- bbatha 4y agoThe paper proposes this as an industrial process to reduce waste and brew time.
- vanattab 4y agoI bet you would get similar results just putting your container of coffee in an ultra sonic clear type deal. Probably a lot cheaper then buying picosecond pulsed laser
- zemvpferreira 4y agoUnfortunately far as I know coffee sonication produces horrible results. If I remember reading correctly the sonication produces a lot of cavitation on the surface of the grounds and leads both to the extraction of horrible flavours as well as the suspension of micro-fines in the brew that never settle. The reputation is it being undrinkable.
- prewett 4y agoHa, this article sounds like some coffee-loving physics grad students procrastinating on their thesis, and their professor said, hmm, maybe we can publish this! When the Mentos + Diet Coke thing was first a big thing, a friend of mine who ran a biotech firm (so was always writing funding proposals), submitted a proposal for an aerosolizer using a similar process, as a mass dispersal system for the military, if I recall correctly. Don’t know if it ever got funded, though.
- titanomachy 4y ago“Mass dispersal system” is a euphemism for “chemical weapon”, right?
- kurthr 4y agoNot the same, but pretty post apocalyptic: https://youtu.be/BHiWygziyso?t=943 https://youtu.be/BHiWygziyso?t=943 Devil's Toothpaste
- anon84873628 4y agoThere are several groups focused on coffee research. Lots to learn about taste perception, extraction dynamics, fluid flow, etc. And because the coffee market is so large, any discovery can have a big practical impact.
- midislack 4y ago
- peteforde 4y agoLast year I backed a project called Osma. https://drinkosma.com/ https://drinkosma.com/ It uses acoustic cavitation to extract flavor and caffeine from coffee without any heating in about one minute. I use it every day and I like it. I love the strong flavor of cold brew, and my stomach appreciates the lack of acidity. There is a learning curve but if you're a HN reader, chances are the amount of experimentation required to dial in your version of perfection is an upside, not a downside. I paid less at the time, but today the kit is selling for US$695. Note that as with all things coffee, it's only as good as your grinder. I ended up pairing my Osma with a Sette 270: https://baratza.com/grinder/sette-270wi/ https://baratza.com/grinder/sette-270wi/
- clairity 4y agoi'm honestly baffled by the cold brew fad, as every cold brew i've tried tastes like the day old, cold coffee that it is, not rich and nuanced like freshly hot brewed coffee. but i'm with you on the grinder. i have the sette 30 and it's fast and consistent, with little waste. i primarily do single serving grinds for brewed coffee with it. the gearbox broke but baratza sent me a new gearbox for free (i believe there was a manufacturing defect in the early models). i got the 30 (the number of grind settings) because i wanted it primarily for pour over rather than espresso. the great thing is that the grind adjustment mechanism can be upgraded (along with the controller faceplate to get presets) and effectively turns the 30 into the 270, which i may do if i ever decide to get an espresso machine. edit: i also got the courser burr, taking the grind size up to roughly a medium grind, which is perfect for pour over. the included burr is better suited to the fine grind needed for espresso.
- atoav 4y agoI am not a food snob in any sense, but cold brew tastes very different from old coffee. It is not even close.
- eyelidlessness 4y agoI agree, and I don’t much like cold brew. I’m not particularly a snob about brewing methods (I use a French press out of pure laziness exactly as a recent article making the rounds suggested), but I do have a snobbery about beans (light roast, generally natural process fermentation). I don’t think I even dislike cold brew per se, I think it’s just often wasted on nondescript coffee so there’s not much flavor to distinguish. Now I’ll gladly destroy any hipster cred I might have accrued saying the above: I do quite like stashing half a pot of yesterday’s coffee, in an open pint glass, to make iced coffee for the next afternoon.
- seanhunter 4y ago...or you can just make a French press/cafetiere using cold tap water, put it in your fridge overnight and in the morning plunge it and run it through a drip filter. It's not complicated, the equipment is super cheap, and the coffee is delicious. To the extent there's a surprising secret, the coffee will taste better if you grind it fine like espresso rather than coarse like you normally would for French press/drip coffee.
- ngcc_hk 4y agoAre you for real ?
- seanhunter 4y agoYes. I know the idea of making coffee using lasers is super-cool. I'm just making sure everyone knows how to make cold brew, because it's really nice.
- krageon 4y agoIf you've already fixed it in a french press why follow that up with a drip filter?
- seanhunter 4y agoBecause if you use fine-ground coffee some of it will go through the filter on the french press and give you sludge in the bottom of your coffee.
- rvrst 4y agoThis is prime Ig Nobel prize material.
- funstuff007 4y agoHot (or Cold) Take: Coffee preparation rituals exist because atheists are looking to replace theology-based rituals and traditions they have forsaken.
- exabrial 4y agoRight tool for the job award goes to these guys