Heat Retention, Clever vs Bonavita Immersion

Coffee preparation techniques besides espresso like pourover.
mikemaddux

Postby mikemaddux » Jan 02, 2019, 8:59 pm

I switched from the Clever to the Bonavita under the assumption that porcelain would hold heat better than plastic. I never bothered testing. Then I saw this video by Scott Rao wherein he recommends the plastic V60 over the ceramic and metal ones.

http://www.youtube.com/watch?v=c0Qe_ASxfNM

He claims that the plastic V60 holds heat best and recommends proving it to yourself by touching the sides. So I tried that with the Clever and the Bonavita. To my surprise the Bonavita was a lot hotter to the touch, implying it was seeping heat out more quickly than the Clever.

I did a test with a cooking thermometer. I performed the following with each brewer. From a variable temperature kettle I used 200° water to preheat the brewer. I emptied the brewer and then filled it again with 200° water. I immediately inserted the thermometer. I noted the temperature at 1, 2, 3, and 4 minutes. Here are my results.

Clever
1 minute - 190°
2 minutes - 183°
3 minutes - 178°
4 minutes - 175°

Bonavita
1 minute - 186°
2 minutes - 181°
3 minutes - 175°
4 minutes - 169°

Since I had already performed the touch test I wasn't surprised that the Bonavita lost heat faster. But I was surprised at how quickly heat was lost in both cases, and especially in the first minute, even though the surfaces were preheated. Also, this test was performed without coffee, and maybe I ought to perform that test also. I would think the temperature would drop even faster in the first few seconds as heat is transfered to the coffee as well as to the surfaces.

At any rate I've now switched back to the Clever, but I'm thinking of looking for a clean (no sludge) immersion brew method that retains heat better than either of these. Perhaps an insulated French press with a paper filter?

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yakster

Postby yakster » Jan 02, 2019, 9:03 pm

Siphon?
-Chris

LMWDP # 272

mikemaddux

Postby mikemaddux » replying to yakster » Jan 02, 2019, 9:07 pm

Good idea. I actually have a Yama stove top, but I've never tested the slurry temperature. I'm guessing it would stay pretty hot with the hot air bubbling through. Another experiment!

EddyQ

Postby EddyQ » Jan 05, 2019, 12:32 am

mikemaddux wrote:I did a test with a cooking thermometer. I performed the following with each brewer. From a variable temperature kettle I used 200° water to preheat the brewer. I emptied the brewer and then filled it again with 200° water. I immediately inserted the thermometer. I noted the temperature at 1, 2, 3, and 4 minutes. Here are my results.


Did you use the lid? The best insulation is air and if it is free to move it will take heat with it. And since the hot water also is evaporating and taking heat with it, there is likely a lot more cooling when left open.

Plastic and porcelain conductivity is quite different, but comparing conductivity to the air around the outer surface, the air is the real insulator. And with slight movements of air, you may get different results.

The porcelain likely has a lot more thermal mass. Once heated, it likely won't change temps with the same flow of heat. But did your pre-heat have enough heat to bring it to 200F? With plastic, perhaps it hit equilibrium temp at higher temps?

Thanks for the data. I only have the Bonavita and am also curious which would do best.

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redbone

Postby redbone » Jan 05, 2019, 10:28 am

I have both units. Clever maintained heat better only if the Bonavita was not preheated otherwise the Bonavita porcelain is more heat stable.
Between order and chaos there is espresso.
Semper discens.


Rob
LMWDP #549

mikemaddux

Postby mikemaddux » replying to redbone » Jan 05, 2019, 5:32 pm

My results were different, but it was only one test.

Bob_M

Postby Bob_M » Jan 05, 2019, 6:56 pm

Check this out. At the onset Scott says plastic is better cuz u don't feel heat when u touch it. Makes sense to me.

http://www.youtube.com/watch?v=c0Qe_ASxfNM

mikemaddux

Postby mikemaddux » replying to Bob_M » Jan 05, 2019, 7:18 pm

That's what got me started (see my original post). I performed the touch test and the Bonavita was much hotter.

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redbone

Postby redbone » Jan 05, 2019, 8:24 pm

Beyond heat retention it's all about what it tastes like in the cup. Same taste after many evaluations. Considering similar taste and similar process of using both I prefer the Bonavita at home for its non staining surface and ease of cleaning. The CCD has a place at work as it more portable and less susceptible to breakage. Can't go wrong with either based on taste. The choice is more of a preference vs performance.
Between order and chaos there is espresso.
Semper discens.


Rob
LMWDP #549

Bob_M

Postby Bob_M » Jan 05, 2019, 8:28 pm

Robert I have both also. Bonavita preheated used at home. Clever for travel.