Brew your coffee with boiling water - coffee brewing temperatures explained.

I just wanted to have a cup of coffe and now I'm involved in somekind of cult :- /

[@raulsuhett]

Haha I feel the same!

[@UWI-Anna]

LOL!

[@filipposgeragidis3993]

I just wanted to be in a cult and now I’m drinking 2 cups of coffee a day

[@Merloc909]

@@filipposgeragidis3993 LMAO....talk about missing the bus...good one though!

[@DamianSzajnowski]

Not again! .__.

[@gcs7817]

It’s like watching Attenborough for coffee

[@thijsvandervoort8261]

If this is true, his channel would explode when Sir David Attenborough passes away because you need a classy, British man in your life somewhere.

[@hattgeorge]

This comment made my day. Thank you!

[@hattgeorge]

"Given approproate temperature and abundance of brewing space in the filter -the coffee thRRRives!"

[@BH-2]

I was thinking, he does sound like someone familiar and yes he is the Attenborough for coffee 😂

[@cinemaocd1752]

Yes! He has Attenborough's posh hoarseness.

[@donhall-aquitania1025]

Thanks, you saved me 45 seconds of waiting for my boiling water to cool. That adds up over the years!

[@ahmadnategh6740]

save time. see world!

[@KingKodra]

@@ahmadnategh6740 are you saying See the world or Sea World?

[@alex.r.g]

sadly you used up your time for this comment. and me too :D

[@embryjj1]

@@KingKodra Why waste time say lot word when few word do trick

[@chookchack]

Lol saved me a couple of grams of water i use to cool off a little bit. It also adds up for all those years.

[@ElJaf17]

You know what...? I have had to return here to say a big thank you to James Hoffman. Now, a year and bit on from switching to home brewing speciality coffee in a French press, it was the basics on water quality, water temperature, grind size and freshness presented by this man that I have ended up following. I bought a glass kettle, I filter water to go in it, I had a French press already, I bought a Hario hand grinder for 35 quid and I buy speciality beans medium roasted. For the price of 2.5 high street coffees I get to drink better coffee than high street coffee for a whole month. Life-changer you are, sir!

[@yahyeet3694]

what is high street coffee? I'm guessing it's coffee from places like Starbucks and similar coffee franchises

[@Julzaa]

I have probably the same hand grinder, what setting (clicks) do you use for your coffee? Preferably filter/chemex/v60

[@ScrupulousAtheist]

So true, Mr Hoffman is a wealth of information.

[@fattony6299]

I'd previously heard and read from numerous sources that boiling water 'burns' the coffee - thank you for explaining why that can't be true. I love your engineering-style approach.

[@IdeaStudioBKK]

Great video! I would love to see you brew the same coffee, same ratio at varying temps from 85-93C and explain the differences in taste.

[@KNURKonesur]

+1

[@PlanckRelic]

Also extraction percentages if James feels up to it. I expect the flavor might change with the total amount of extraction as well as the balance of that extraction, both of which might be changing with brew temp.

[@psychedelious]

in my experience, coffee taste differently as it cools down. maybe that's how they got the recommended temp? what i would like to see is a comparison in taste of say something brewed @ boiling pt and something brewed around 90 C and compare their taste when they cool down to, say, 60 C

[@matalebi]

I did this test with a light roasted single origin coffee and i can confirm it made a noticeable difference in taste. Also I noticed once the beans get passed 4w from roasting date, lower temperature made the taste backed to normal again. For me dialling the temperature to adjust the flavour/taste to my liking is a key and apparently it varies with different beans.

[@dehto5]

@@psychedelious our taste buds operate the best with food/drink in 50-60'C range, but as Hoffmann said for the chemical reactions we call "coffee brewing" to happen at the most optimal level we seek to use water 90-100C.

[@gradypicinich2404]

Love your videos, James!! I would like to point out one statement, however, as a chemist. While you are correct that warmer water has more energy to facilitate interactions in brewing, the overwhelming majority of what happens in a coffee extraction does not involve re-action, but inter-action. Dissolution, as you mention, is not an example of chemical change, but a physical change, as the majority of this process retains the chemical identities of the species involved (though there are probably some reactions that occur in a tiny portion). Chemical changes are characterized by the destruction/creation of chemical bonds, which obviously would be rampant during the roasting process, as is evident in the change in color of the beans, as well as the development of new flavor compounds (though not all of the changes are chemical during roasting). Thank you for your expertise and testing techniques; it is something I can greatly appreciate in my own lab!

[@EdElliott]

True, but also (as a chemist) temperature plays a huge role in solubility limits _and_ the time it takes to dissolve a material (just try making simple syrup with cold water sometime...).

[@gradypicinich2404]

@@EdElliott I definitely agree with you, I do pharmaceutical formulation work and I run into issues like that all the time. I just think it is important to maintain the distinction between reactivity and interactivity 😎

[@mylesricker3095]

super cool to learn ty '_'

[@toddcote2710]

Water temp changes when the boiling stops & hits the room temps! Aka " change in temperature " this is my inter thought process before watching the video!

[@toddcote2710]

@@telanis9 lol. Didn't you comprehend the video? "Coffee brewing temperature explained " how complex do you want it?? Unsolved mysteries did a whole episode on it back in the early 90's you should check it out, it's fascinating! Cheers!

[@bluesfool1]

So I'm guilty of thinking that boiling water was going to be to hot and make my coffee taste bad. You just saved me 30 seconds of cooling time for every cup I make from now. Thanks!!

[@indianOutlaw87.5]

I dont even drink coffee on any kind of regular basis but i still love this channel

[@BRZDR]

This was amazing to watch. I am a Motorcycle Camper and I bring a silicone pour-over filter stand for my morning coffee. I could never figure out why my camping coffee tasted better than from my machine at home, maybe it was a placebo. I like a Medium-Light Roasts for a smooth black coffee. I pour with boiling water and would get the best results this way. Fascinating that I had been lucky enough to have a brewing method that was correct! I would have been miserable with dark roasts, not being able to figure out the proper extraction.

[@luispires7069]

These videos that go into the “technical” side of brewing coffee are just so, so great. And two videos in two days, what’s this, Christmas? What’s next, for tomorrow an AeroPress technique video? 😄

[@jameshoffmann]

Sadly not - but there might be one more video this week...

[@luispires7069]

James Hoffmann one more video this week, we’ll gladly take it! 😄 it’s funny that after I started using both the V60 and/or a French Press as my daily drivers (following your methods on both), I kind of got scared of using the AeroPress... so simple, but at the same time, it allows so many variants, it’s truly a coffee brewing “toy”!

[@kyoshimadoshi]

@@jameshoffmann its the Siphon video I hope. Save the filter one for next week

[@mihir1997]

@@jameshoffmann will we get an aeropress brew guide ever? I remember you saying you might do one.

[@JuicedBrah]

Mihir G was thinking this too! Definitely needed

[@Wolverine3660]

I have always brewed coffee in a French Press, first in a glass french press( like the one James used in today's video) and now I brew in a Bodum double-walled stainless french press. I have tried brewing with water at 85 deg Celsius, and with water at 100 deg Celsius. I buy my coffee from a local roaster who roasts my preferred Ethiopian coffees to a light city roast, and I have found that the coffee brewed with water heated to 100 deg Celsius tends to taste better and fuller than coffees brewed with 85 deg Celsius water. Thanks, James.

[@skyechrystal]

I have been a barista for over 10 years and absolutely love watching your videos (and reading your book). Not only are they informative, interesting and incredibly calming, they also put me in the best mood. I love learning new things and your passion for coffee and curiosity is wonderfully captivating. Thank you James! From one bean to another, thanks for being so badass!

[@user-fw8wt4qo3o]

Sounds like you need to find a grown up job.

[@reuireuiop0]

@@user-fw8wt4qo3o while your remark tells us someone is on the lookout for something less sour

[@user-fw8wt4qo3o]

@@reuireuiop0 the only thing sour here is your breath

[@hideehere]

@@reuireuiop0 maybe they'd be happy with my burnt moka pot coffee

[@ChurroWaffles]

@@user-fw8wt4qo3owhy what’s wrong with being a Barista? Sounds like you need to grow up, period.

[@GreyhawkRC]

recently I was brewing and tried to reach a 90-93C temp in my kettle to pour in to my French Press... this makes sense now. My focus doesn't need to be so hard on the water temp as long as it is boiling. Absolutely love all the videos. I've learned so much about coffee in the last few days than ever in my life. So nice to have the processes explained in such great detail.

[@markrichards6863]

I wonder if anyone makes an insulated french press.

[@reguluscaius4636]

@@markrichards6863 there’s lots of them, Bodum Colombia is one, ikea also makes one, the original Espro is insulated. Personally I like glass ones because I can see if the coffee grounds have settled into the bottom.

[@robinbanks9691]

@@markrichards6863 yes. Bought one at a thrift years ago. It was wide at bottom with non skid rubberized bottom giving way to enameled stainless body tapering smoothly to top. It had a sturdy handle. It was a travel mug sold out of Montana. Made in China no doubt but I loved it.

[@pd10642]

This man is one of the least pretentious, most genuine, most enjoyable reviewers of anything I have ever seen. Thank you!

[@canadude6401]

I come for coffee making advice... and leave with ASMR-like voice of James that calms me the f%$# down. win-win.

[@havingicecream]

His voice is really very soothing!

[@ashabussurur4532]

His british accent too is a top notch

[@canadude6401]

I've heard many people say he needs to do a podcast, or at the very least work for Audible voicing audio books. **please and thank you James?**

[@wm.jordandent9242]

Lol yeah, when James says not to worry about something I actually stop worrying about it, not everybody's like that...

[@NastyaKireeva]

Same, I actually watch his videos before I go to bed. 🙈

[@radioclash84]

Either this guy is Youngest looking Old Man I’ve seen or the Oldest looking young Man I’ve seen.

[@RLuik]

That's his charm 😆

[@MrVerces]

Either way sounds someone old to me

[@HylianPirate278]

He’s 40 (or 39, one of the two)

[@joeydoesthings4955]

TheBrignad as a 40 year old, I sometimes feel old, and sometimes feel young! 40 is a weird age!

[@RecklessFables]

@@joeydoesthings4955 same at 47, TBH. Walk 3 days a week for an hour and manage your weight and it is fine. Add more exercise and you can feel 39 all to way to 50.

[@moldyketchuphead]

The proof is in the taste. After trying a pour over using James's method straight off the boil, I get a better tasting coffee particularly with my favorite light roast.

[@starry_lis]

I found that for medium roasts his as-hot-as-possible V60 rule doesn't work quite as well.

[@johng9562]

James was the 2007 World Barista Champion for a reason ~ he knows his stuff.

[@Austin-nk2uu]

I even reboil mine throughout the pour over lol

[@225byakuya]

Raphaël Atherill in the video description, he specifies that medium roasts is recommended to be 2 degrees cooler. Maybe try that and see if it makes a difference

[@dhmacdonald8605]

I was going to comment to say something similar; I'm a new V60 user and I've been getting disappointing results with a home-roasted Yirgacheffe (lighter roast) and have found that brewing at or above 97 C (208 F) yields much better flavour--at least for this particular roast. I was using lower temps before yesterday and found it tasted bland and almost papery, despite having rinsed the filter. I can see myself giving temperature more consideration moving forward.

[@brotendo]

This is something that has always been so intuitive to me. Everyone tells me not to heat the water past a certain point, but I always assumed that as soon as the coffee is poured, temperature starts to drop. Even more so once it hits the coffee grounds, the filter, etc. I've always brought my kettle up to 100 C.

[@jeffumbach]

Yep without the heating source as soon as you mix it with another substance the overall mixture will be at a lower temperature. The only way to get the slurry to boiling was if it was being actively heated the entire time.

[@brotendo]

@@jeffumbach Finally someone with some sense!

[@AxelCalvet]

Thank you so much! I am French and yes the typical French roast is way too dark. Lowering the temperature of water did improved greatly my daily coffee. Thanks again. You improved my life on a daily basis!

[@Clampyclamp]

Thank you!! Wonderful advice. I usually take my kettle to 94 degrees but went to 100 after watching and my coffee has never been better. Wish I had not spent a small fortune on my thermostat controlled kettle when any old kettle that goes to boil works just as well. Live and learn.

[@nocturnus009]

Apologies James: I was kinda happy to hear the use of slurry. That might be a function of being an environmental engineer focusing on water & wastewater but DETAILS!

[@Awesomeness156]

I'm in the same field and I thought the same thing!

[@narason9940]

Same here! My major was Environmental engineering and even in Korea we use that terminology lol

[@pjwade86]

I haven't an issue either. Civil engineer checking in, with concrete slurry 😂

[@dorak2518]

Hi mates, it seems like environmentalists are coffee lovers. Here is one more coffee lover from environmental field

[@narason9940]

mhPhillip Wade you know what? My major was civil engineering when I was freshman haha then changed to Environmental one lol

[@IanButterworthyyc]

Don’t forget altitude. I’m at 1000 m where water boils at 96 C.

[@antonioriojas8299]

Ian Butterworth Yeah, at 2,300 m this is a non-issue for me - wish I could get the temperature higher, as it boils at ~93 C.

[@calebschwarz1529]

I'm at 93.8°. I would love to hear tips or tricks for high elevation brewing.

[@QoraxAudio]

To me, altitude is a non-issue. I live at -3m altitude lol

[@SojournerDidimus]

@BIGFOOOOOT that would only ensure that the water would rise to 100°C, once the cooker is opened up the water will boil (lose energy through evaporation) until it's back at this 93°C

[@dylannorthrup5439]

Just an idea... but, the dual walled stainless steel French press James referenced does exist... I’ve bought a couple from Starbucks, and they are great. With pre-heating and boiled water, you should likely be brewing around 90-93°C like the rest of us.

[@kellytaylor3915]

I use the pour over method of brewing coffee. I have a ROK hand crank burr grinder. I normally set my electric kettle for 190 f. After watching this I tired setting at 212f and the coffee seems more bitter to me at 212f vs the 190 F I normally use. So everything being the same except temps. I have to say I prefer the 190F over the 212F when brewing using pour over method of brewing. To me the coffee is a bit smoother less harsh if that is a proper way to try to describe the taste difference. Your videos are very well done. I have found that the roast of the bean and area where grown need to be tried at different temps to see what brings out the best of each. Happy Brewing.

[@DamonFavor]

I feel so much better about my years of using a simple kettle and not checking water temp. I don’t just boil and pour but it’s usually less than a minute after my kettle switches off that I’m brewing. Thanks for the insight!

[@Acontinouslean]

Thank you! Something I've been saying for years . Max out your kettle , the Brewer and grounds rob so much heat. Also if I see a cafe using a hot water tower for pour over set at 200-205f, buy the batch brew.

[@erythuria]

"Aggressively pre-heating" - and I can't help but imagine roaring as I pour.

[@Anthropomorphic]

I hear it helps with degassing.

[@erythuria]

@@Anthropomorphic preventing degassing has always been more of an issue for me...

[@dgh6g33gf]

Roasting your roast

[@prussianmillionaire5055]

Lol

[@mannequinparty]

Rouring. Poaring?

[@racoonzattack]

7:17 My friends when they see me come out of quarantine in shape.

[@susanredna688]

omg lol

[@chicoktc]

oh shit perfectly done hahahahahahahah kudos to you

[@fortheloveofchocolat]

ROFL...

[@OwlsEyelash]

Hahaha!

[@jokkerBANG]

Waited for that moment with anticipation. Worth it

[@yourfriendshipisafog]

So I was using a pouring jug, a thermometer and a standard, non-variable temperature kettle with my aeropress. I was using 80-85 degree water based around the various methods I had seen posted. Just drinking my first cup straight from the kettle, and, if anything, it tastes slightly better. Thanks James, you didn't get your thermocouple out in vain.

[@ericmalmstrom9943]

Thanks James, great job! That's by far the best explanation on water temps I have seen. When people say that you're "burning" the coffee with boiling water I know they don't know what they are talking about.

[@sulaimanaljanahi6855]

Wish you could do a video exploring the relation between TDS and taste; a lot of coffee bloggers justify their lower temps on specialty medium roasts by saying they don't care about TDS and that it just "tastes better" so it would be interesting to see you dissect that topic. Thanks!

[@danjv]

Thanks for this James. I always thought that burning my coffee with hot water was laughable. I've been brewing my pour over straight from the kettle with great tasting results. One of your contemporaries brews at 207° which is a bit over 97c in his Café.

[@leopoldbloom4835]

15 minutes after the upload: 1408 Clicks, 47 comments, 181 likes, 0 dislikes. The James-Hoffmann-Coffee Nuts at their best! 👏🏻

[@JohnnyWrongo-b9l]

The word "slurry", for those who have lived on or close to farms, is an unsavoury word or rather it has unsavoury associations. I needed this info, Thank you. I no longer need to worry about whether or not the water is too hot.

[@SCFick318]

Yeah I can’t do 100C with the beans I use, it did make it very bitter to the point where it tasted like chemicals and water. I do around 87C and that gets me a really nice flavor and finish. Just as a heads up to people who might be experiencing this problem as well if you just started brewing with pour-overs like me

[@RonPaulgirls]

WHAT BEANS DO YOU USE AND HAVE YOU EVER TRIED MEDIUM ROAST WITH NEAR 100 C

[@inthebrokengravity]

Also, just bought a v60 kit and I’m so excited! Next step is getting a coffee grinder yay

[@brekkoh]

you have entered a dark, coffee scented hole, from which I'm afraid there is no recovery... btw I have the commandante c40 i use with my v60 and it's a dream, an absolute dream.

[@JayPFrancis]

Don't forget to check your local resale shops for a burr grinder for not much money. You might get lucky.

[@inthebrokengravity]

Stu Dunn oh I’m willing to take the risks haha and thank you for the suggestion! Imma look that one up

[@TacticalSatsuma]

Haha, I'm in the same position, everytime I go into a shop now my first thought is "ooo I wonder if they have any coffee stuff..."

[@Straightfromshibuya]

I’ve been using the breville grind pro for 2 years and love it. I’ve used the Baratza encore and it’s good it’s just not as intuitive and user friendly as I would like. The birds on the Baratza are incredible though

[@vamos419]

From my experience of making coffee since the last 8 years, I agree that boiling water doesn't make coffee bitter. Maybe people feel that way because they drink the coffee while it's too hot and don't let it cool down to taste the sweet notes. If you're using light to medium roast coffee, water should be as hot as possible. I always pour it straight off the boil and I get the sweetest cup everytime. If I lose some temperature on the water, my coffee always turns bitter.

[@GreenTeaViewer]

mindblowing

[@zio_tungst3no297]

What about putting the brew vessel in a microwave (if possible) or in a boiling water bath? That would easily allow you to reach 98+ degrees..

[@MorrisDugan]

@@zio_tungst3no297 Or boiling coffee in water in a pan on the stove?

[@89robbied]

I would have expected taste test at the end, Even at a small difference on the thermostat many say it has an effect.

[@Cameron167]

I did too, but it would mostly be for effect and presentation. I'm sure he taste tested different temperatureswhile developing his v60 brewing video. Probably before that as well.

[@lellefot]

@g0phuckyourself Depends on what he means. If he means a temperature probe that is dipped in the slurry during brewing, then yes, that is a thermometer. If however he is referring to the temperature setting on his water boiler, then that is in fact a thermostat.

[@lellefot]

@g0phuckyourself The point of the video was never in question. It demonstrates that the temperature in the slurry while brewing is lower than boiling water. The statement Robert posed above, however, is in relation to taste differences depending on small variations in temperature of said brew slurry. Now in order to achieve those differences (to see if that statement is accurate), I would say the best way is to standardize the method of brewing, and then simply vary the starting temperature of the water, which would be quite easy to achieve by adjusting the thermostat on the boiler.

[@kraigkent3809]

@g0phuckyourself he said "many say it has an effect". It would be moronic for those who say it has an effect to measure with a thermometer every day. They (like myself) use a variable temperature kettle and set the thermostat differently to test how the brew improves (or not).

[@poutama16]

Would have caused some channelling I’d imagine

[@SooperFlye]

I've been a _regular_ coffee drinker for nearly 40 years. *No latte's, espresso or cappuccino.* Just plain old-fashioned coffee. Since the start of the pandemic I've gotten more involved in the coffee making process. Bought a *French Press* for the express purpose of saving money and to avoid people during the pandemic. Once I discovered *James Hoffmann* my relationship & attitude & philosophy with & about coffee has changed in a big, big way. _Thank You Mr. Hoffmann._

[@thecolonel4551]

I love a French Press, and I like hot coffee in the cup. I pre-heat both my press, the cup and use a rich dark roast (yum!) - I am retired from the military, please appreciate the "variable" coffee quality I experienced in 30 years 🥺. Using water as close to 100c as possible is also in my recipe. I further adjusted my steep time to prevent over extraction👍. Glad your results showed - as long as extraction and grind are properly adjusted, it's just a matter of your taste preferences (no damage to the coffee). Love your work!

[@monochr0m]

Oh wow, I was randomly recommended this video and jesus your way of talking is soothing

[@rd5933]

I’m totally over the moon, now that I found your channel! You’ve shared thousands of logical and scientific informations I need to know since I’m a complete newbie. thanks ever so much for your educating videos, James! but I’ve got to admit that your voice is somehow gives me an eargasm, yet sometimes it’s also a lullaby for me 😂

[@alexcereuceta5907]

Since I discovered your channel, I have improved my extractions and my results, my wife and I already had most of the necessary gayest but didn’t quite have the knowledge down. Thank you for demystifying sooo many misconceptions. Loving my chemex everyday more.

[@christianwischnewski8109]

And with "gayest" you mean "gadgets"? ;-)

[@alexcereuceta5907]

Christian Wischnewski yes!! I apologize. Autocorrect took over

[@DLysergicAcid]

Mr Hoffman, This is the first video and definitely not going to be the last video I've seen by you. You have amazing way of articulating what the facts are. I give you an A+ and appreciate you.

[@fdranderson]

I'm new-ish to your channel James. I cant believe how much there is to know and learn about coffee, grinders, pots, machines, filters ...! You are great to watch and learn from thanks!

[@jerryparhar5810]

Thanks James. You saved me from spending money on a new kettle with a temperature display.

[@tkjho]

James made much more sense than most other "coffee experts" who merely repeat what they heard without giving it a thought. I myself brew finely ground coffee with water boiled on a stove-top and poured right into the grounds in a carafe. Then I sit the carafe on top of the turned off but still hot stove-top heating element and keep stirring for a couple of minutes to prevent the grounds from settling down on the bottom and get burnt by the element. I use finely ground coffee to make sure that I can extract as much as possible from it. After about 5-7 minutes, I'll let the coffee grounds settle down and carefully pour off the coffee. The coffee tastes better and has more body to it than filtered coffee. Coffee gets burnt and bitter after sitting on the keep warm plate of a drip coffee maker because the stationary bottom molecular layer in contact with the glass bottom gets a lot hotter than 100ᴼC and get burnt, stirring it would prevent this from happening.

[@frankypc]

"Little bit hotter...but not a lot hotter" James Hoffman ,you should sell shirts with that quote haha

[@Thekidfromcalifornia2.0]

I would buy it haha

[@verykiasu]

Was thinking the same thing. Make it a meme!

[@Beakphoto]

I was about to say that has very high meme potential.

[@Thee_Sinner]

How I feel when I eat a salad once a month

[@canadude6401]

Time to create a Merch offering on your channel James!

[@jimmorgan6213]

These videos are really superb; I wish I’d found you sooner. I spent the first third of my life at 5-6000 ft., and the last two thirds at sea level, but I didn’t start drinking coffee 'til I’d come down in the world, so I can’t report how coffee brewed where water boils at 94-95 °C would taste by comparison, but all the temperatures you measured would be reduced by 5-6 °C at those elevations, and I doubt I would have enjoyed coffee nearly as much as I do now. The taste of espresso wouldn’t be affected as much, probably, and it’s hard to see what could be done to rescue pourovers, yet vacuum pots (what you call siphons - I think infelicitously) would at least get you back to the temperature regimes of sea level pourovers.

[@Vortex1988]

Lol, I'm really happy I found this video. I just started getting back into coffee again after a long stint of just settling for Keurig, and I was wondering about this today as I was making some French press coffee. I was never able to totally figure out my French press when I first got it years ago, and I thought it was because my water was too hot since I didn't have a thermometer at the time. No matter what I did, the coffee always came out sour and acidic. Fast forward to today, and I've been tracking temperature more closely, always making sure the water in the kettle is between 195F and 205F. Then I started thinking about how much heat the water may be losing in my French press, so I did a test with some water in a mug as well as taking temperatures from the French press as I poured into it. I quickly realized that the water cools down much faster than I ever thought it would, and I determined it couldn't be the temperature throwing the taste off even when I wasn't monitoring the temperature closely years ago when I first started. I've had much better luck adjusting my grind and dosage sizes, and I'm happy to say that I'm very close to where I want to be now. I'm going to try increasing the dosage by a gram or two tomorrow in order to see if that's where I need to be, because I think I have the grind size down. I'm just trying to get the coffee just slightly more viscous at this point.

[@Jonas_Fox]

I think you need a tasting temp blind showdown!. Mark the bottom of identical cups; brew cold, really hot, and normal hot. Let all cool to room temp and taste all to see how each tastes. Another great video. Thanks for sciencing for us.

[@bobtheyob]

I have noticed with instant coffee it tastes better if you add milk or cold water to the granules, stir it into a sort of paste and then add your boiling water. Give a try, the worst thing that can happen is you waste a spoon or two of instant coffee :) I've had a number of people comment on how nice it tastes when I make it this way at work. Then again people do if I make cafetiere or filter coffee so I suspect I might have a knack for it.

[@lesliekorodi70]

takes lot of time and energy

[@tristo931]

Thank God being telling people this for ever that you can't burn coffee with hot water

[@GR19611]

Scold.

[@cryptocanon5742]

Found your channel couple of days ago and since me and my GF have 5 coffeshops in Thailand I find it intresting, you are very knowledgable, anyhows I am from Finnish origin and lived in Sweden as well, the coffee culture between Fin/Swe is very similar, yes small differences but not much, in both countries we have something called Kokkaffe/Keittokahvi and we use grounded coffee that is coarsely grounded and the coffee is added directly to the pot that is then boiled for abt 5 minutes and just let to be afterwards, so that the coffee beans sinks to the bottom, which after the coffee is served, this was the only coffee I ever knew when I was a kid. "The old people" still prefer this style of coffee, sadly its not fashionable today. So with that said I agree that even when boiling the coffee it doesnt get bad or burned or what ever. The burned coffee comes if you let it be on the stove and let the water evaporate. My 5 cents Have you ever tried this kind of coffee ?

[@ilenegloss9216]

I like how you present the information, very informative. Just bought a French press, never used before.

[@samtoshner8002]

Hi James, have you explored the effect of water's pH on brewing? In my experience with chemistry, pH can have a very dramatic effect on what compounds are extracted. Some compounds go from completely soluble to completely insoluble in the difference between distilled water and tap water. Not to mention, as most folks are aware, basic solutions will tend to taste bitter and acidic solutions will tend to taste sour, so the resulting brew's pH level will almost certainly affect its taste.

[@fetzie23]

It isn't just PH, but the minerals that are already dissolved in the water that can change its flavour considerably (some are PH-relevant, some remain even if you change the PH of the water). Beer brewers at large breweries (think Heineken, Warsteiner, Stella and so on) often start with distilled water and then add various salts to it so they have water that produces a beer which always tastes the same. Manufacturers of soft drinks don't just pull water from the tap either, because they need the product to taste identically, no matter where on the planet (hell, even in the country) it was made. For example, I love the taste of the tap water where I live (lots of minerals in it, hardness scale is off the chart, even with an ion exchange filter we have to descale the kettle every month or so). When I go to stay with the grandparents, I can't stand the taste of their tap water (their water in incredibly soft, with barely any minerals in it at all).

[@opulentElephant11]

Is there a recommended video to see what the best water profile is for say a general dark roast? I would be interested to know. 🤓

[@joyfuljaj]

@@fetzie23 I heard James Hoffman say to always use soft water for coffee. Do you find your hard water does okay? I don't have any kind of water softener and get decent coffee. I hate the amount of mineral deposits in everything in the house though, so I should probably look into some kind of system.

[@fetzie23]

@@joyfuljaj It does okay after running it through a filter to take out most of the hardness. That’s not done for flavour though, more to stop the kettle and coffee machine dying every other week due to limescale buildup 😉

[@joyfuljaj]

@@fetzie23 thanks for the quick reply. Is your filter an add on to your sink, fridge, or a household system. The only people I know with hard water filters have the big softeners with salt and the works. Even something to keep the scale out of my kettle and coffee pot would be nice. I'm surrounded by lime quarries!

[@brettsuydam]

Living in Colorado: Water boils here at ~96-98 C, and that's in Denver. Plenty of people make coffee at much higher altitudes. I'd love to see a recommendation episode for brewing coffee at high altitude (we have to modify baking, so I would think we should have to modify brewing as well).

[@threestans9096]

the temp is more important than the bubbles. i’m pretty sure.

[@brettsuydam]

@@threestans9096 That's exactly my point: the temperature of water won't get to 100 C unless you put it in some sort of pressure device. Instead of saying "one can only have good coffee at sea level" I'd like to see the best coffee results at different altitudes. Coffee is a mountain berry after all.

[@androssgetzko2098]

@@brettsuydam James didn´t say that you get bad coffee with lower temperatures. He just say´s that your water temperature should be as high as possible. If it´s 96°C it is fine. His Water kettle itself couldn´t get to 100°C....

[@wahrebeobachter]

How about using a percolator? It needs to reach boiling temperature to work and is considered to be outdated as 100 degree celsius is not the ideal temperature to brew coffee. But in higher altitude, it could one of the best tool.

[@saiyansaif6605]

Use pressure cooker for boiling the water as inside the pressure cooker pressure is much higher and water can get beyond 100°c without getting converted to steam and after that just use that water to brew ur coffee (* a little catch here, now matter what u do, 98°c is the highest temperature u gonna get at this altitude so i would say just brew it for a couple of more minutes, that way it will be able to extract most out of ur coffee Have a good day :))

[@EdwardIglesias]

I've always suspected it was just not that big a deal. At least not compared to the quality of the coffee, the grind, the water etc. Also, I'll be in London next week and hope to try your Square Mile coffee.

[@marianedmond5326]

Before I watched this video, I experimented with boiling water. Had a Brazilian Mantiqueira de Mina roasted to around "medium dark". I had been brewing this in my Chemex with 191 F water, but decide to try 212 F. Took 2 good breaths for courage, bloomed it for about 30 seconds then did a gradual continuous pour over. Cound not believe the flavor change. It was so good. Thank you.

[@coffeetutor1]

This is super, James, I'm so glad you did this. Your video also helps to explain/simplify water temp for cupping coffees. If we pick up a kettle that is boiling, by the time we walk to the cupping table and start pouring, like your French press demonstration, we're at an appropriate temperature for "cupping-roast-level" coffees. Many people, when learning cupping, ask about the water temperature "standard", but practically speaking, when you have dozens of coffees to cup, using the "just off the boil" method works great and is an efficient way to make sure all sets of coffees are evaluated at the same temp (as long as you use one off-the-boil kettle per set).

[@brekkoh]

In the future I would like to see an exploration of brews at various temps but otherwise identical conditions in a blind cupping scenario.

[@jameshoffmann]

I've done this in the past, at work. It's sort of interesting - the coffees we tried were all pretty nice from 85C upwards, but got better and better the hotter we went.

[@jong2359]

@@jameshoffmann That is really the main point of all this, I think. Hotter generally means tastier to most people that actually like coffee. There is no such thing as too hot when the boiling point is the ceiling.

[@JimShealy]

@@jameshoffmann So what you're saying is that hotter is better... what about above 100C? You'ld need a pressure vessel to do it, but I'd be interested where the curve of tastiness starts to go back down.

[@ohreallybigdeal]

Am also curious about the interplay of temperature vs. smell. Would lighter molecules escape faster with the higher kinetic energy? In an open brewing system where the air is not confined, can there be an optimal point where a good amount of (good-smelling) molecules are retained, while extraction is maximized? Is there a brew device that allows us to trap the smell with good extraction? Or the best strategy is just to extract and then instantly lower the temperature of the brew?

[@lucassch.3761]

@@JimShealy @James Hoffmann I think you have to put your lab coat back on!

[@iancrawford4977]

I love how accessibly scientific you are 👌 keep up the amazing videos and info!

[@yupp9393]

I didn’t dislike the word “slurry” before this video. However, way James said it with such contempt and disgust has left me perturbed.

[@John-X]

Lol, who is James? We are watching Steve Coogan talk about coffee, not this "James" person.

[@jimmilstein7166]

Hoffman doesn’t like mucilage either, but it’s my favorite word.

[@sMASHsound]

moist slurry

[@PhillipAlcock]

If you you were brought up in the country and know what pig slurry is, then you might have a similar reaction 😂

[@BrianSantero]

@@sMASHsound Thank you. I came here for the moist slurry.

[@ronniefromdk]

I had been meaning to measure the temp of the "slurry" in my french press suspecting a lot of energy is lost to heating up the vessel. This saves me the trouble. Brilliant!

[@leonordin5366]

YOU'RE AN INSPIRATION! I love watching your videos and refuel my excitement of pushing further in the Industry

[@VoodooChi]

My father is a chemist and coffee lover, and he claims that the reason coffee which has been kept warm tastes bitter is because the compounds which makes the coffee tastes good evaporate at a lower temperature than water. So if you leave your coffee warm and exposed to air, the aromatics will go away and you'll be left with only the bitter, burnt taste of the compounds which do not evaporate. Hence, the idea of burning coffee. This taught me two things. 1. Use a closed vessel (such as a thermos) if you plan on keeping coffee for a long time, . 2. If you make iced coffee, cool it down as quickly as you can when it's done.

[@sMASHsound]

what led me to search this topic is i usually microwave my coffee. when it starts to overflow, then i stop. but i suspect it doesnt get up to 100deg c. my microwave stopped working so i hand made two times on the stove. the first, i poured it out just as u see bubbles. those initial bubbles are really dissolved gases escaping the water as soon as it gets enough energy for the vapor pressure to overcome the partial pressure, which is way before 100deg c. the second time i made, i let it come to 100deg c where u get the rolling boiling water. that gave it an very burnt flavor. so i do suspect now, that between 85 and 90 is a good temp for coffee. now that i learned that it doesnt burn the coffee, but the high temp water causes to good flavor compounds to boil away, and causes the burnt flavors to leech out.

[@512bb]

Your father sounds like a man of wisdom to me, makes complete sense to me.

[@VoodooChi]

@@Ziraya0 Right, that certainly makes sense. I have no idea how it works, I just regurgigated what he said a couple of years ago. :)

[@markrichards6863]

I never thought about it, but that may be true. I am a fan of cold brewed coffee. It has a much mellower flavor.

[@shrutisingh1405]

Thanks

[@katiie7]

When I make mine in a french press I always put in about 2 inches of cold water before I put the hot water in 🤷🏼‍♀️ I like it because it seems sweeter and more flavorful. If not it’s bitter

[@hxhdfjifzirstc894]

Katie • I use one cubic inch of clear ice, but you might not be that sophisticated.

[@davidbeddoe6670]

Try wrapping it in a wool scarf and hat and throw in the coffee about 5-10 minutes after the boiling water. Let it sit longer to steep too. It'll blow you away.

[@rblossey]

a well-extracted espresso is kind of a "slurry with a fringe on top" 😉

[@SigEpBlue]

This was very well done! I use a calibrated thermocouple and meter with my own coffee-making setup, always allowing the kettle to automatically shut off (at 99 °C), and then cool to 90 °C, at which time I'll pour it over fresh grounds in a single-cup carafe and filter. I've found that for my particular water, coffee, and personal preference, this is as hot as I can go before the less-desirable flavors start coming out.

[@BansheeBunny]

0:57 This is solubility rate. Solubility is the ability of a substance, the solute (coffee), to form a solution with another substance, the solvent (water). The concentration of any solution, increases with temperature. This is why cold brew takes so long. Cold brew is the movement from a high concentration to a low concentration through a semi-permeable membrane, the effects here also increase with temperature (warm rooms brew faster). Edit : If you make coco from a powdered mix and find undissolved mix at the bottom of your cup, add more solvent (milk/water) or increase the temperature of the current solution. Dark roast beans are larger in size and lighter in weight than light roast, when ground they take up even move volume. This increased volume adds surface area, that in-turn increases solubility rate. This video helped me with the solubility rate for different roast levels and avoid over extraction.

[@BeanHoppersCraftCoffee]

This was great. I always had better results with hotter water in the French press. The off boil trend is pretty new in the industry.

[@havingicecream]

I love science, and I absolutely _adore_ when food-related youtubers talk foodstuff science!

[@williamhaniszewski1462]

I would love to see a video on diagnosing brewing faults, such as over extraction, based on taste. Not really sure how this would work since taste is so subjective, but it would be helpful for trying to dial in grind settings and ratios.

[@mellie4174]

yes!!

[@peternikitopoulos8776]

Well done. I will no longer worry as much as I used to about temperature. Your experiment provided some very interesting learning. Thanks again.

[@paulcarlton598]

The best intro/outro music of any youtube video. Chill/trip hoppin' and head boppin.

[@kylehovey6532]

Some things that might make this a bit more scientific: show the temperature of the water as measured by the same probe before you pour it, show the temperature of the brew setups with and without coffee grounds, explain what reactions go on when coffee is brewed, and at what temperatures (I think things dissolving into solution isn't technically a chemical reaction), mention your elevation and barometric reading, and another cool thing would be to see how different spout geometries and pour heights affect your brewing temp.

[@mrmax35]

“The ultimate syphon technique” video would be awesome! Great video btw

[@griplove]

Wow that was really quite cool. I started bringing up my water temp once I started hearing this idea, but I’ll be honest up to now I’ve been too chicken poop to go full boil. Thank you for this! -Joe.

[@GadgetsGearCoffee]

I love James' content and admittedly, have fallen asleep to that gentle quiet voice

[@Healing70x7]

Game-changer video! I've always heard that you can't use boiling water, but I've tried both ways, and I ended up preferring it and still using boiling water. Now I know I can continue.

[@MrTacticalinuit]

I've heard water flavor changes at the boiling point, which is why tea brewers insist on having sub-boiling temperatures when they brew their tea. It would be interesting to see a coffee test where one is brewed at 80c, and one is brewed at 80c after cooling down from boiling.

[@breadnoodle]

(i know this is 2 years old but anyway) Most teas are brewed with water that's around 90-96°C (96°C is basically fresh off a boil) with the exception of green teas where 80°C is the cut-off. Due to the way they're produced (fresh leaves are heated up quickly after harvest to deactivate enzymes subsequently stopping oxidisation) they still contain a lot of the bitter compounds present in fresh leaves. Dropping the temperature to 80°C helps you avoid extracting too much of them so you don't end up with a bitter cup. if course this is just a general rule and there can be exceptions

[@murselduz6520]

❤

[@nickolaypalamarchuk4100]

What about stove top methods? Coffee in pot, tukish coffee and the percolator. You can get a 100°C and even more in this case. The temperature question is much more important in these methods!

[@hondsvod]

Don't know the physics behind it but avoiding burnt coffee in a moka pot is key

[@kaizer694]

I would've liked to see the temperature of the boiling water in the kettle with the red temperature sensor. The lower values might be due to an inaccuracy in the sensor.

[@SuperbadXx]

Get this man to the top!

[@drpowerthirst9093]

Cheap K-type thermocouples, which I suspect is used in the video and the kettle, have accuracies of +/- 2 °C. If the kettle is actually 96 °C (205 °F) instead of 98 °C (208.5 °F), then James is still within the temperature recommendations you see in most guides (30 seconds off boil, which is about 96 °C). I don't think a difference in 2 °C/3.6 °F really changes his point.

[@kaizer694]

@@drpowerthirst9093 Even so, when doing a scientific experiment, one should always control for their measurement. The sensor could be defective. The boiling temperature could be different due to altitude variations. The list goes on. The point is that it would've been very easy to make the control measurement to remove such doubts.

[@sparks6177]

@@kaizer694 it’s a bonavita kettle they are notoriously accurate and have been the gold standard kettle for the past 10 years maybe longer, I highly doubt the kettle is more then 1 degree off

[@csanton3946]

This dude has got an amazing talent of explaining things. Gets my attention. Its like having decent convversation with someone

[@butterfly531]

I've always been using boiling water to brew coffee in a preheated french press... using medium roasted beans.. fine grind but not too fine. The result is always smooth and flavorful.. never burnt tasting. I've always been wondering why it's not harsh tasting with boiling water. Thank you for doing this temperature testing. :)

[@dcashley303]

Yeah, I've generally found that light roasts that are typical for filter coffee do taste better when you really preheat the equipment and use high 90's water. I used to think 80-85 was best but I just kept making it hotter and it just got nicer. I think preheating is really important though, especially the ceramic V60 I use. I pour around 150ml or boiling water through it fairly slowly to make sure it gets as hot as possible. This changed my coffee dramatically. Kinda shocked by the drops in temperature here though, between the kettle and the brewer. It makes me feel a bit calmer in that I'm not likely to actually make the brew *too hot*.

[@Joeyrietveld]

I used to do this, but switched to the plastic v60's. I found that when pouring on hot water, the outside of the plastic ones still aren't very hot to the touch. To me, this would mean a plastic V60 isolates much better and prevents heat loss? Not sure if it's entirely true but brewing in the plastic ones with water around 96 to 98 degrees actually makes light roast filter coffee taste very good.

[@dcashley303]

@@Joeyrietveld Yeah I think even James mentioned that in his V60 video. I am tempted to pick up a small plastic one when I next stumble upon it just to see the difference.

[@ginodc5944]

Requesting a review of cowboy coffee, where you boil it for a few minutes. I might actually try it tomorrow but would be interested in your analysis. Apparently boiling takes out the bitterness. What else does it take out?

[@tiffanyrose2396]

"Mucilage is probably worse" ... another priceless moment.

[@rhughes1795]

This is purely my opinion and I may be wrong. I think that coffee tastes scorched when heat is applied after it has been brewed (like from the heating plate under most pots, etc.). I won't even microwave a cup that has chilled a bit, it seems like it takes on a scorched flavor if I do. Again - no science, only my observations while drinking my less-than-perfect coffee to begin with -LoL . Thanks for the great vids . I'm grateful

[@Reolos1]

Thank you, Sir. This has been a concern of mine as my kettle has no governor, and you have sufficiently laid my mind to rest.

[@joshkrohn7442]

This is very interesting, James. I've seen that higher temperatures allow the water to pass through more quickly (reducing extraction time). I'd be curious to see how dramatically temperature affects extraction time and total extraction, because while the solubility increases with water temperature, I'm not sure how much the rate of solution changes. I'd love to know more about this. Graphs would be awesome!

[@pr0faker]

What we are missing in this is if the taste is worse with this very hot brew or not, so a tasting would be a good addition to this test. Maybe even test light or very dark roasted with hot and just warm water for tasting.

[@curtislevey7639]

I see your point but I wouldn't expect James to give this advice without tasting it. And given this is how he brews everything himself I would think he would have noticed if it tasted worse and therefore avoided

[@Eldrake]

186°F for an Aeropress. Trust me. Tested all sorts, that's the sweet spot.

[@littlebrookreader949]

I well remember my mother’s volcano coffee, temperature wise. - also my grandmother’s, the same. I was convinced they had no skin left in their mouths. I woke up mornings to the kettle whistling on the stove. Another good one, James! 😎

[@madamfirefly1]

Thank you! I usually V-60 with water temperature 90°C. Sometimes I experience with 85-86°C. A bit different taste but I still like it. Your video is very helpful.

[@themeatpopsicle]

Imagine all these people with refractometers that aren't even using a temperature probe in their slurry

[@TheVideoGuardian]

Do people seriously try to use refractometers for coffee...? If so, I hope they at least have one with active temperature compensation...

[@antoniogranatelli5280]

Technically, the making of coffee is a solid-liquid extraction process. We typically do not call it a reaction in chemical engineering.

[@isaiahperez1115]

Is that because it does not fall into the 5 main types of chemical reactions like combustion, double replacement, etc?

[@antoniogranatelli5280]

@@isaiahperez1115 - It’s a separation of a substance from a matrix.

[@outofthenorm5087]

5th, I've been early for a video, twice in a row. Your rock Mr Hoffman. I love your videos!!

[@outofthenorm5087]

Yay, a heart from my KZbin idol. You rock Mr Hoffman!!

[@MrSpike77777]

Thanks, going to give this a try. I've always waited 30 seconds before the first pour.

[@petersdotter1]

Changing from cold water (recommended by manufacturer) to hot, not boiling, has improved my American ground brand a lot. Thanks.