Moka Pot Brew Temperature

Coffee preparation techniques besides espresso like pourover.
jpender

#1: Post by jpender »

I've been brewing moka pot coffee lately. Like for a month. One hundred shots later and I can say this: While I had a number of good, rich tasting shots, I don't really like moka pots. It's ironic that the country where espresso was invented likely has the highest per capita ownership and use of this ill-conceived device. It's Italy's percolator.

After all of those moka pot shots I got out my Bialetti Brikka, which is also a moka pot but one with an important modification. It took two shots to dial it in and the cup was head and shoulders above my best effort with the standard 3-cup Moka Express I'd been using all month. So much easier!

Then, again using the same coffee, a fairly forgiving blend, I pulled a shot on my Robot. I guessed at the grind and the first shot was, oh, maybe twenty times better than what came out of the Brikka. I sort of wish I could take that month back.


The reason I got out my Moka Express 3 in the first place was to measure how varying six parameters affected the finishing temperature. Specifically, I looked at:
  • water fill amount
  • dose
  • tamped/untamped
  • initial water temperature
  • stove setting
  • grind
The results more or less confirmed what I'd already believed but it was still interesting to see.
These things made the brew finish hotter:

more water --> hotter
more coffee --> hotter
tamping --> hotter
hotter initial water temperature --> hotter
finer grind --> hotter
higher stove setting --> hotter

I installed a temperature sensor and a level sensor in my pot. The temperature sensor was just below the lower screen to measure the temperature of the water just before it enters the grounds. I also observed and noted the time when the liquid coffee first emerged. In the graphs below the thicker parts of the curves represent the same "portion" of the fluid flow, ranging from when the coffee first emerges to when the bottom water reservoir has only 35g of water remaining.










After all of this I spent a little bit of time trying to dial in the perfect moka pot cup. But I ultimately failed despite trying several strategies. I could get okay cups pretty easily and sometimes a very good cup, relatively speaking. Nothing fabulous seemed within reach. And I had plenty of sink shots that had that "moka tang" astringency that comes from too high a final temperature. Maybe I don't know what I'm doing. It doesn't matter as I have my Robot. Espresso is way easier than moka.

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ojt

#2: Post by ojt »

Interesting, thanks :) Will try some of it myself too, though I tend to use the moka pot for a similar reason as italians: it's simple. When I do use it I don't care too much about the result, as long as it ain't bitter. My go to technique has been to use hot initial water and an ice cube in the server.

Here are tests done by Lucio, also a member here on the forum:

https://caffettiere.blogspot.com/2020/0 ... -moka.html

Based on your tests and those by Lucio I really need to try "letto bagnato" again... but like you said, other methods are just superior. Frenchpress, V60, espresso.
Osku

jpender (original poster)

#3: Post by jpender (original poster) »

Thanks for the link with Lucio's more recent measurements. I was thinking to experiment with his wet coffee method but for convenience I decided to place my probe below the puck. Most of the temperature reduction in his method must come simply from reducing the amount of water in the tank. You can clearly see from his tests and as well as mine that it has a strong effect on the temperature. But without embedding a probe in the puck I couldn't measure what effect wetting the grounds has.

I used to drink only moka pot coffee. For at least 15 years that's what I did. I usually bought beans at Peet's, had them grind them for me, and then kept the ground coffee in the freezer. I would love to be able to go back in time and try the coffee my younger self brewed. Would I spit it out??

jpender (original poster)

#4: Post by jpender (original poster) »

I want to apologize to whomever I offended with a poorly chosen word in my original post. I only meant to poke fun at Italians, not any other group. But I should have known better. I am truly sorry.

Jonk

#5: Post by Jonk »

I see you've tinkered with this before: The secrets of the moka pot - How to video

The best "moka" I've had was with a Bellman. Thanks to the valve you can kind of pre-infuse and let the puck steep for a while before opening it the second time. Had some smooth, velvety cups that way. Seems to work best with Italian blends (who would've thought? :wink:)

..but it's a crapshoot - like you've shown small changes affect the results and I'm inclined to agree it's not a reliable way to brew good coffee (mostly the very opposite, only to be tolerated with milk)

Did you measure EY this time around? In your old posts the grind was quite a bit finer but only the finest had a good yield.

jpender (original poster)

#6: Post by jpender (original poster) »

Yes, I used a moka pot for a long time. And I've spent many hours measuring them in the past. I like playing coffee scientist in the kitchen.

I thought about measuring extraction yield but I don't have a quality refractometer. I can get precise results by dehydrating 10-15ml samples but it's too tedious for doing dozens of samples. And my wife is working at home because of COVID and she hates the smell of coffee. I couldn't subject her to a month of that. :-)

I've long wished for a VST and a mini centrifuge but those items would cost as much, if not more, than all my coffee gear combined. I could afford it. It just seems way out of proportion.

I couldn't find details on the internal structure but it appears to me that the Bellman is similar in concept to the Brikka. One big difference is that you control the valve with the Bellman. I'd love to play around with one.

Before the Robot I was reasonably content with the coffee my Brikka produced. It never made overheated, bitter/astringent coffee. I didn't have to screw around with it to get it to work well, other than adjusting grind and brew time. And unlike my regular moka pots I didn't feel like I had to stick with darker roasted blends. I usually brewed medium roasted African SOs in my Brikka. But... espresso is better. It just is.

ojt

#7: Post by ojt »

jpender wrote:And unlike my regular moka pots I didn't feel like I had to stick with darker roasted blends.
This is where I disagree a little :) Now, I can't remember how the Brikka was (had one like 15 or so years ago) but exactly because of the overheating nature of the bialetti express I feel it is better suited to brew medium to light roasts. In fact I sort of rediscovered the moka pot after I dropped into the espresso and specialty coffee rabbit hole.

For darker roasts I prefer stainless steel pots such as the Giannina which seem to run cooler, but that is the only one I have tried.

Should look around if I can find a cheap Brikka somewhere :)
Osku

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ojt

#8: Post by ojt »

Oh and since you have the gear, you could try the ice cube trick. Preheated or cold water and then add a cube or two of ice in the server while brewing, see what that does if anything. This an oft repeated tip even by specialty roasters and other professionals here in Italy, and I have to say I've had some pretty good brews. Yeah it's still not espresso of course. Would be good I guess if the probe was inside the coffee bed in this case.
Osku

jpender (original poster)

#9: Post by jpender (original poster) »

Ice cube where? Do you mean the top of the pot? What is the reasoning behind that trick? And why would it affect the temperature of the coffee bed?

Charlemagne

#10: Post by Charlemagne »

My experience mirrors yours. I played with moka pots for a few years with rare success, and eventually bought a Brikka. The coffee was better, but still not amazing. I'd only use it when I wanted to make iced coffee quickly.

Then I got a robot and the Brikka has been collecting dust ever since. As you said it's way better in every way. Even though the Robot costs 10x the Brikka, it's certainly worth it for me.