You have to love the internet - everyone loves to make accusations with nothing to back it up , and enjoy the security of hiding behind a computer where no one can call them on it, and their identity can remain hidden.

With that said, I had a comment posted on a video stating "You're cooking that coffee with all the friction from that hand grinder.". How much truth to this is there, if any? The Kyocera that I and many others have, has ceramic burrs, as do the Hario's that some are starting to use for their pour-overs - but the difference it takes to grind between a machine with ceramic burrs and these hand grinders is significantly different. What is your take on this?

I would guess that is the other way around. The risk of burning coffee should be bigger in an electric grinder. Since you turn the burr A LOT slower in a hand grinder, heat build up should be minimal.

But that is not much more than a guess

I think that the design on the burrs has more to do with the potential "burning" of the coffee than the speed of the burrs. Those here adept at thermodynamics can comment on that, as well as the total heat energy (BTUs, Therms, Joules, etc.) created in the process.

Even if it gets to 300 degrees, if there isn't enough energy to make an ant lift his (or her) foot and say, "That's a bit warm!" (assuming ants could communicate verbally in English) then it doesn't matter much.

..ya, it's the weekend.

Since he/she chooses to hide behind their YouTube account, and won't dare show their HB user name, here is their latest offerings:

"Actually yes...In an electric grinder the coffee comes in contact with the burrs for what 2-3 seconds...Your grinding for minutes at a time.Friction is friction and you're cooking that coffee even before you brew it."

"and before you go into "it takes longer to grind by hand than with elect" rap I know,I have the same grinder as you (Kyocera).

Im not trying to pick a fight with you,so dont go crying on HB about posts you dont like."

Dave measured the temperature of the grounds during the Titan Grinder Project:



The folks at Counter Culture Coffee also measured the exit temperature of the grounds using an infrared thermometer during the evaluation of commercial grinders (their interest was how much coffee was heated during continuous use). IIRC, it peaked in the low 100°F's.

Though I've never measured, given that a manual grinder turns much, much more slowly than an electric grinder, it's got a lot longer to dissipate heat; I would expect the grounds to be heated less, especially because manual grinders don't see continuous use, so there's little retained heat in the chamber shot-to-shot.

Anonymous wrote:Im not trying to pick a fight with you,so dont go crying on HB about posts you dont like.

I'm lazy, resorting to a thought experiment supported by a few tidbits of experience. If you or your youtube commentator want to raise the level of discussion, post measurements and an explanation of how you measured. Otherwise, you may as well agree to disagree and move on.

In a blind cupping someone can really tell the difference enough to care?
I can compare a Dienes to a Major for two 15 gram grinds in a row with an IR in the morning. I'll try to measure the burrs too.
The Major and Dienes each have their own great qualities they add in the cup and I can't ever think of heated grinds being a factor.

With a handgrinder (or an electric one for that matter), the amount of heat (energy) you generate should be the same, no matter how long it takes. Going slower is not going to create more energy. But, going slower will allow the heat more time to dissipate, so going slower should be cooler, not hotter.

Randy

Maybe those hand grinders cook the coffee enough to roast it. I think I'll skip the roasting step and just slowly, very slowly for maximum heat grind the green coffee.

As Randy wrote, the heating over time argument doesn't really hold up, but leaving all that aside, how does the coffee taste?

Too many people on the internet approach coffee through their heads and start willy waving about the logic, when they should be using their tongues - and not to talk....

HB wrote: Otherwise, you may as well agree to disagree and move on.

Well, it seems this is what it has come down to. It would have been nice if they could have shared their thoughts in this thread though.

michaelbenis wrote:Too many people on the internet approach coffee through their heads and start willy waving about the logic, when they should be using their tongues - and not to talk....

Best statement ever!