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A comment on Deconstructing Kitty.

Re:Deconstructing Kitty by mannykannot on Tuesday May 22, 2018 @09:46AM (#17125873)
This is a great example of how much information there is in the design of even simple things, the way in which one design decision constrains others (why not an iron core? Because the magnet would tend to stick to it. But why a magnet? So we can push it. But why push it? Because it is easier to tell when the bob has just passed bottom then when it is about to get there) synergy (with a magnet, we can use the induced voltage in the coil to measure the movement) and KISS (a simple knife-edge bearing.)

Another reminder to make my code as simple as possible.

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Re:Deconstructing Kitty by madeofpalk on Tuesday May 22, 2018 @09:57AM (#17125940)
This reminds me of rice cookers, which seem to work like magic yet are actually crazy simple devices - just a simple thermocouple that shuts the pot off when the temperature reaches above boiling point (meaning there's no more water left to be absorbed/turned into steam).

It's the sort of thing that means that even super cheap rice cookers from the supermarket work great - that's all I've ever used.

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Re:Deconstructing Kitty by teachrdan on Tuesday May 22, 2018 @12:26PM (#17127155)
This is brilliant--way simpler than my mental model of how my Zojirushi makes perfect rice every time.

Link for the lazy: https://www.quora.com/How-does-a-rice-cooker-know-when-the-r...

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Re:Deconstructing Kitty by madeofpalk on Tuesday May 22, 2018 @12:50PM (#17127341)
yes! this is the quora link that finally explained to me how it worked
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Re:Deconstructing Kitty by clairity on Tuesday May 22, 2018 @02:55PM (#17128471)
yes, thanks for the explanation!

i was just saying to a friend that the simple rice cookers (seem to) cook faster and make rice just as well as the fancy models but did not have this explanation in mind to back that up.

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Re:Deconstructing Kitty by JasonFruit on Tuesday May 22, 2018 @11:11AM (#17126438)
Why do they have separate settings for white and brown rice?
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Re:Deconstructing Kitty by jonknee on Tuesday May 22, 2018 @11:25AM (#17126583)
Cheap ones don't. More expensive ones do and it cooks at a lower temp for a longer time with a better end result.
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Re:Deconstructing Kitty by jandrese on Tuesday May 22, 2018 @11:51AM (#17126841)
Brown rice setting just turns off one heating element, otherwise it works exactly the same.
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Re:Deconstructing Kitty by seszett on Tuesday May 22, 2018 @11:26AM (#17126598)
I don't know any cooker with a brown rice setting, but this setting should probably first turn the heat on, then turn it down and let the rice sit below boiling point for a while, then turn the heat back on (though not as much as with white rice).

It could still wait for the heat to suddenly rise in order to know when to stop.

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Re:Deconstructing Kitty by marak830 on Tuesday May 22, 2018 @09:43PM (#17130934)
For standard long grain white rice, 1 part rice to 1.2 parts water. (Rinse rice until mostly clear water comes out), put on the heat(no lid/cover) until it just starts simmering(and I actually mean the preboil simmering). Heat to extremely low and lid/cover on. Timer for 10 minutes. After the timer goes off, heat off and timer for 12 minutes. Don't open the lid/cover at any stage.

That's how your rice cooker makes absorption style rice, and how you do it in a pot. (Also a ton better than boiled)

Source: 18 year experience chef ;-)

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Re:Deconstructing Kitty by JasonFruit on Tuesday May 22, 2018 @11:44PM (#17131337)
What about shaking the pot from time to time to keep the rice from adhering? I've read that frequently but not seem it do anything in practice.
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Re:Deconstructing Kitty by marak830 on Wednesday May 23, 2018 @02:53AM (#17131882)
Don't need to, if you follow what I said, it will come out perfectly fluffy.

Also note I have made a mixture of multiple types of rice, same way, with no issue.

Honestly I only actually learnt the Asian method about 5 years ago and was kicking myself for not researching it earlier. It's so much better and insanely reliable across different types of rice.

Edit: after it is done I tend to take the lid off, stir it and let sit for a bit to let it air out. That helps a lot.

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Re:Deconstructing Kitty by wrycoder on Wednesday May 23, 2018 @09:07AM (#17133805)
My method is similar, except that once it boils, I stir the rice once and then simmer on medium high heat until the water level gets down to the surface of the rice and steam pockets (“rice eyes”) appear. Then reduce heat to lowest and cover for 20 min.

I’m going to try your fluffing method.

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Re:Deconstructing Kitty by marak830 on Thursday May 24, 2018 @10:39AM (#17144376)
Do, I'll give yours a go as well. Always looking to learn new methods!
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Re:Deconstructing Kitty by masklinn on Tuesday May 22, 2018 @12:45PM (#17127288)
> I don't know any cooker with a brown rice setting

Zojirushi's, depending on the model. Mine has settings for white rice, brown rice, sushi rice, porridge and quick cooking.

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Re:Deconstructing Kitty by repsilat on Tuesday May 22, 2018 @09:50PM (#17130951)
> below boiling point

Could also be "at boiling point but at a lower power setting".

When at boiling point, each ml of evaporated water takes some amount of energy, it is not just a matter of time. Power at boiling point is basically "boiling rate".

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Re:Deconstructing Kitty by seszett on Wednesday May 23, 2018 @02:23AM (#17131794)
Yes, but brown rice needs to sit in warm water for a while before being cooked. If the water is at boiling point during this time, it will have boiled away before the rice is finished cooking.

The reduced power setting during boiling (relative to white rice) is for the second phase of cooking.

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Re:Deconstructing Kitty by masklinn on Tuesday May 22, 2018 @11:22AM (#17126561)
Possibly bowl temperature or some form of cycling? Maybe send an email to zoj's support to ask them? (not all rice cookers have different white/brown settings, but I know they do)
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Re:Deconstructing Kitty by raverbashing on Tuesday May 22, 2018 @11:48AM (#17126820)
Brown rice usually takes longer.

Source: cooks rice

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Re:Deconstructing Kitty by madeofpalk on Tuesday May 22, 2018 @12:05PM (#17126952)
Time isn't a factor here though - it takes longer to cook 10 cups of rice than 5, but it still uses the same setting. As I mentioned, these rice cookers don't use a timer.
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Re:Deconstructing Kitty by jonknee on Tuesday May 22, 2018 @07:04PM (#17130195)
Some fancy rice cookers do more than just use a thermocouple. You'll see them advertised as using "fuzzy logic". The brown rice setting uses a lower temperature and takes quite a bit more time than the same amount of white rice. There is also a timer, you can it to have the rice done at a certain time.

See this popular model for an example:

https://www.amazon.com/Zojirushi-NS-TSC10-Uncooked-Cooker-1-...

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Re:Deconstructing Kitty by the_unknown on Tuesday May 22, 2018 @08:24PM (#17130584)
The Amazon gods seem to be playing pranks on me at the moment: I use your link to look at the product on Amazon US "Zojirushi NS-TSC18 Micom Rice Cooker and Warmer – 1.8 Liters"

Clicking the link on the page to view the product on Amazon Canada gets me to "Zojirushi NS-TSC18 Micom Rice Cooker and Warmer, 10 cups"

Strange, The US site lists the Liters held while the Canadian site switches to telling me how many cups it can handle.

Ergh. I'm Canadian. I can handle the litres.

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Re:Deconstructing Kitty by protomyth on Wednesday May 23, 2018 @10:10AM (#17134288)
Fuzzy Logic is actually quite nice when doing heating and balancing using a fuzzy control system. Lotfi A. Zadeh invented it, and I learned it from several books by Earl Cox. Fuzzy Logic is well worth studying.
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Re:Deconstructing Kitty by marak830 on Tuesday May 22, 2018 @09:46PM (#17130939)
> it takes longer to cook 10 cups of rice than 5

Aside from a short time to heat a larger volume of water, it doesn't. (and your really not talking that much time difference lol).

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Re:Deconstructing Kitty by madeofpalk on Wednesday May 23, 2018 @05:34AM (#17132622)
"Aside from the part where it takes longer, it doesn't take longer"?
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Re:Deconstructing Kitty by marak830 on Thursday May 24, 2018 @10:39AM (#17144372)
You're talking such a slight variable the point isn't worth belaboring.
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Re:Deconstructing Kitty by wpietri on Tuesday May 22, 2018 @11:21AM (#17126535)
The complementary lesson I take from it is that I have to seek simplicity while iterating in real-world conditions. This isn't a from-first-principles kind of simple; you can see that perspective in a number of those questions. It's the kind of simplicity that respects the complexity of the real world instead of denying it.
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