
The battle to invent the automatic rice cooker - pseudolus
https://www.atlasobscura.com/articles/rice-cooker-history
======
spaceflunky
The science behind a rice cooker is fascinatingly clever, yet painfully
simple.

In short, boiling water temperature plateaus due to the latent heat of
vaporization. When the water is gone the temperature of the pot starts to
rise. The rice cooker uses this principle to control the switch. The switch is
held by magnet. When the pot finishes boiling the heat rises and exceeds the
curie point of the magnet, which means the magnet ceases to be magnetic, and
the (no longer) magnetic switch is released turning the rice cooker off.

Here’s a great video explaining how it works.

[https://youtu.be/RSTNhvDGbYI](https://youtu.be/RSTNhvDGbYI)

~~~
throw0101a
> _When the water is gone the temperature of the pot starts to rise._

Water-to-rice ratios are important. America's Test Kitchen has a good video on
the topic, especially if you're using a pot and not a rice cooker:

* [https://www.youtube.com/watch?v=JOOSikanIlI](https://www.youtube.com/watch?v=JOOSikanIlI)

* [https://www.youtube.com/watch?v=DJFU7ezipbg](https://www.youtube.com/watch?v=DJFU7ezipbg)

The rice actually only 'needs' a 1:1 ratio, but you need to put in extra to
deal with evaporation; brown rice needs more-extra because it takes longer to
cook (the bran slows absorption), and the longer cooking time leads to more
evaporation.

TL;DR: ignore what's on the bag/box, and for every cup of rice add one cup of
water (1:1, 2:2, 3:3), and then a fixed amount of extra overhead for
evaporation.

~~~
gbear605
The traditional method in a lot of Asia (per what I’ve read online) is to put
a finger on top of the rice pointing down, so that your fingernail is touching
the rice, and to fill water up to your knuckle.

~~~
yissp
Wouldn't this result in different amounts of water depending on the dimensions
of the pot?

~~~
tzs
Evaporation rate should be proportional to surface area, so the volume of
extra water you need to add to make up for that should also be proportional to
the surface area too. Adding extra water to a fixed depth accomplishes that.

This is assuming a pot with straight sides, at least above the lowest water
level during cooking.

~~~
firethief
> Evaporation rate should be proportional to surface area, so the volume of
> extra water you need to add to make up for that should also be proportional
> to the surface area too.

This would be accurate at room temperature, but under stovetop conditions
wouldn't evaporation rate be determined mostly by the amount of heat energy
added to the water?

~~~
folknor
Both, and more.

In my experience, the surface area where evaporation occurs has the most
impact. If I know (and obviously I do every time, just measure it) the
evaporation area size, that's what I use to dial in how much pre-boil wort I
need the first few times I use a set of equipment.

But heat energy is the second most important factor. Sea level, salt/mineral
levels, and other factors are - in my experience - not worth considering. But
I've not tried to brew beer on the top of a mountain.

I've brewed over 300 batches of beer in vessels of various dimensions
(including surface area and evaporation area), and with various amounts of
heat energy, applied in various places in the vessel. Ranging from 2kW to
18kW, sometimes heat applied under the pot, sometimes distributed throughout
for example 3 heating elements at various heights. 2kW for all from 15L to 60L
vessels, 6-18kW from 25L to 120L, and 18kW (IIRC) for 500-800L.

When brewing beer, the boil usually lasts for 60-90 minutes, and the boil off
rate is extremely important for hitting your target gravity and volume, and
getting a consistent result if you're brewing the same recipe again.

What you do as a brewer is you test the equipment on the first 2-3 batches and
then after that you can hit your target boil-off with 99% accuracy every time,
or 100% in an enterprise-grade professional setup.

I've never been more than 5-10% off my estimated boil-off rate for the first
batch, and I only account for surface area in that estimate. Even with 6kW for
25L.

------
ThePhysicist
For people that regularly eat rice, buying a decent rice cooker is really a
no-brainer. Cooking rice in a pan is possible and you can obtain good results
if you're careful and turn the heat down at the right moment before the rice
starts to stick to the bottom of the pan and burn, it's easy to miss though. A
rice cooker makes this process so much easier though: Put in the rice, the
adequate amount of water, press a button, wait, eat (usually) perfectly cooked
rice.

I started with a German brand a few years ago but finally mustered up the
courage to buy a good Japanese one (Zojirushi seems to be the market leader
these days). I imagine that it tastes a bit better now but honestly even most
of the cheap rice cookers produce quite good results. Recently Xiaomi
introduced a series of rice cookers which have really nice induction heating
and a really heavy, solid cooking pan, unfortunately they have littered them
with "smart" functionality, so it's nothing that I want in my kitchen.

~~~
cycrutchfield
IMO the Korean brands are the market leaders. Check out Cuckoo

~~~
nosborn
I was told by a rice cooker salesperson (in Asia) that Korean brands should be
avoided if you plan to cook brown rice. Apparently brown rice isn’t eaten in
Korea so the machines don’t have a brown rice setting.

I don’t know if the former is true but the latter seemed to be on the ones I
saw.

~~~
ffggvv
i’m no rice expert but i really don’t think you need a special cooker for
brown rice in my experience. just a different ratio of water to rice. it isn’t
special

~~~
ginko
Brown rice takes significantly longer to cook, so the rice cooker might not be
programmed to do that.

~~~
brudgers
With the simplest rice cookers, there's no programming. When the water is
gone, it is gone.

~~~
ffggvv
yep, i just add more water and the brown rice turns out fine. though i’m sure
fancy 200 dollar zojirushi ones probably do it better, i’m happy with
simplicity

------
blntechie
Electric rice cookers are pretty uncommon in South Asian countries. Reasons
could have been due to the electricity availability and affordability
initially.

But it has not caught on even now. I have seen electric rice cookers in
minuscule number of households. Based on interactions, it’s more to do with
people not liking the taste of the cooked rice. I always found this funny as
older generation used to complain about the same about pressure cooked and
stove top cooked rice instead of the wood fired stove cooked rice but everyone
have accepted it now.

~~~
unmole
They are fairly common in urban South India.

------
skinkestek
This is just a story I heard when I was a kid, but I think HN might either
like it or have some more details about it :

There's a marketing story about a western company that tried to introduce
their product to the Japanese market with the slogan: "as easy as cooking
rice" \- which, according to the story managed to insult every Japanese woman
as cooking rice was - according to the story - considered more or less an art
form in Japan at the time.

Anyone has details about this story?

~~~
odomojuli
I vaguely recall this story as well, all I've been able to find so far is an
excerpt in International Business that doesn't go too far into detail.

------
chris_st
Note to those who already have an Instant Pot: they make fantastic rice.

~~~
travisjungroth
The trick I found (maybe this is true of all rice cookers) is it's better if
it has time to rest after cooking. I start the rice as the very first thing
when cooking and it works well.

~~~
roganartu
I have found that the perfect amount of wait time is, conveniently, how long
it takes for the natural pressure release to complete after cooking. Normally
that's another 10-15 mins or so, but whenever the pressure lock drops so that
you can open the lid the rice should be good.

I always disable the Keep Warm setting though, not sure if that makes a
difference.

------
grenoire
I don't quite get why people think that pot rice on the stove is somehow
difficult. Measure your rice and water, and set up a timer. That's it.

We've been cooking rice for millennia in this way, a rice cooker is just
plastic waste in the end.

~~~
zeroimpl
100%. The proper measuring of ingredients and timing is all that's required.

Take a look at the first line of the article:

    
    
        Cooking rice on a stovetop can be fraught. Add too much water and you end up with porridge.
    

Then take a look at this line shortly afterwards:

    
    
        These devices can seem all-knowing. So long as you add water and rice in the right proportions, it’s nearly impossible to mess up
    

So in other words, the device doesn't actually solve the most important
problem... The timing isn't particularly important, as long as you remember to
turn down the heat as soon as it starts boiling.

~~~
pmoriarty
You have to get the water and rice in the right proportion in both rice
cookers and pots.

However, a rice cooker frees you from having to watch over it while it cooks.
It'll stop cooking automatically once it's done. Not so for the pot, which you
have to keep an eye on or time, and turn off when it's done.

This difference makes a rice cooker much more convenient for those of us who
want to do other things while the rice cooks, and not have to worry about it.

Also, a rice cooker will keep your cooked rice warm for a long time after it's
done, but a pot won't.

~~~
zeroimpl
Most of the time that I cook rice, I also need to cook something to go with
it. So after I turn on the rice, I then start preparing for the rest of the
meal or just tidying up the kitchen a bit. Usually by the time the rice boils,
I’m still around. Once you turn down the heat, it doesn’t really matter if you
leave it on for 20 or 30 minutes. (40 minutes would be kind of crunchy, but if
you’re going to forget about it that long you probably weren’t hungry and
shouldn’t have put rice on)

Also I use a glass pot which will stay quite warm for at least an hour after
turning it off.

I used to have a rice cooker. But I gave it away to free up counter space. My
stove has 4 elements, but counter space is precious.

The original article describes rice cookers were invented because cooking rice
over a wood fire is very difficult. I’ve no argument with that. But cooking
rice with a generic pot on a modern stove is trivial, and most people buy rice
cookers because they’ve been taught to.

------
sorokod
We have a rice cooker that we use at least once a week.

It has a single lever/switch - when pushed it cooks.

It is over a decade old and works perfectly.

Do yourself a favor - don't buy smart appliances.

------
tradewarsonlyn
Been cooking rice in a microwave for years now. Jasmine, Thai or Himalayan.
Use any rice. Seems to cone out pretty well every single time.

~~~
pmoriarty
What container, rice and water quantities, lids, and timings do you use?

Do you have any tips for microwaving rice?

------
arh68
I am amazed how well my Zojirushis make rice. One can make the same rice _two
different_ ways, consistently (white, umami). No burnt layer, no undercooked
rice. I think the pressure/induction makes slightly better rice than the
standard fuzzy logic; there's no restaurant near me whose rice I'd prefer over
my p/i Zoji.

------
apalmblad
A good discussion of rice cookers, in my opinion, needs a link to Roger
Ebert's (yes, of film fans) article on The Pot:
[https://www.rogerebert.com/roger-ebert/the-pot-and-how-to-
us...](https://www.rogerebert.com/roger-ebert/the-pot-and-how-to-use-it)

------
colmvp
FWIW, I'm Asian and I just use a pot on stove.

~~~
middleclick
I am of Indian descent and basmati has also always been cooked on a pot on a
stove. And once you get the basic things right, it's actually not difficult. I
am not downplaying the effectiveness of the rice cookers, just that it's
possible to cook good rice without them.

~~~
claudeganon
Most rice cookers are designed for East Asian rice and do middling with
basmati. Some higher end models do have settings for it that work quite well
though.

------
julianlam
Owning and using a rice cooker is such a time saver that I am often surprised
that it's not a staple in other peoples' houses (though much of that is a
cultural thing,I eat rice basically every single day)

It's like Americans and not owning a kettle. Boggles the mind, but I suppose
they don't drink as much tea as I do ...

On the topic of _which_ rice cooker to buy, the answer is simple: the rice
cooker was perfected years ago, with its double pot single button (on-off
switch) operation. Anything else is a gimmick and not worth paying extra for.

~~~
tonyedgecombe
On the other hand rice is so trivial to cook on the hob why bother with a rice
cooker?

------
MAMAMassakali
Why not just use pressure cooker? Cheap, easy to use, durable and versatile.

~~~
pmoriarty
I've read too many horror stories of pressure cookers accidentally exploding.

------
enjeyw
Growing up I always assumed a rice cooker was one of those things I'd never be
able to live without - for years my family used one almost every day.

When I moved out of home, I didn't buy a rice cooker initially, because you
don't strictly need one to make rice. I was amazed at how convenient making
decent quality rice on the stove was! It cooks faster, and there's less
cleaning up afterwards.

Many years have past and I still don't own a rice cooker. I'm not sure I'll
ever own one gain.

~~~
summitsummit
I've had the exact same experience.

------
pmoriarty
Just a warning about cheap rice cookers...

About six months ago I bought a tiny $20 model Dash[1].

I've often heard people say that cheap rice cookers are just as good as
expensive ones, and since I'm poor, live alone, and this was my first rice
cooker, I thought it would be enough.

It turns out this rice cooker had a number of problems.

First, the screw that held in the pot lid on this rice cooker wasn't made of
stainless steel, so it quickly rusted.

I could have gone to the trouble of going to the hardware store and picking
out a perfectly matching stainless steel screw (if they had one), but I never
bothered, so to this day I still lift the pot lid with a paperclip that I
insert in to the hole where the pot lid used to be each time I want to lift
out the lid. It's a little annoying, but I can live with it. I'm sure for some
people not dealing with this annoyance would be worth paying more for a
decently made rice cooker.

The second issue is that this ultra cheap rice cooker only makes enough rice
for me to eat at a single sitting. As a single person that only very rarely
has people over, this is enough.. or so I thought until I found that I'd
rather cook extra rice ahead of time that I could eat throughout the week (or
at least one day in advance), so I don't have to even bother with the rice
cooker ever day. As simple as the rice cooker is, it's still a bit of a hassle
to rinse the rice out, and fill the cooker with rice and water. I'd rather
just microwave leftover rice, which is a bit simpler.

Third, the markings for the water level and the instructions for this model
are just plain wrong and take experimenting to get the optimal levels. After
some months of experimentation, I managed to perfect my technique, but it
would have still been a lot less hassle to just have the thing make perfect
rice from the beginning rather than having to fiddle with it so much.

So, because of these issues, in retrospect I wish I'd gone for a larger,
inevitably more expensive rice cooker... and hopefully it would have been less
annoying and fiddly from the start.

[1] -
[https://www.amazon.com/gp/product/B07CHZP91L/](https://www.amazon.com/gp/product/B07CHZP91L/)

~~~
genocidicbunny
I think the actual message of 'Get a simple rice cooker' often gets heard as
'Get a cheap rice cooker' which is not quite correct.

You don't need a rice cooker that has two dozen different functions and some
'Neuro Fuzzy Logic' crap. But you do want a well-built rice cooker that wont
break down and rust on you.

Your best bet for a decent cheap rice cooker is your local asian market. The
bigger ones will likely have quite a selection, but even your dinky little
chinatown grocery store will probably have something quite usable.

------
jeffrallen
Alton Brown taught me: No single taskers in the kitchen, except for the fire
extinguisher. I don't see what's so hard: put in rice, wash it, fill cold
water to one finger joint above the rice, boil, cook slow 7 mins, turn off
leaving covered, wait at least 5 more mins while finishing sauce (but up to
15!), fluff, serve.

Pots are for cooking. Machines are for other stuff.

~~~
oehtXRwMkIs
Many believe the rice cooker to be an exception to this, especially when
you're cooking rice for your family every single day. It's just easier, and
when you do something constantly, even minor improvements help save time and
effort.

I think you have to follow the no unitasker rule in moderation. If you eat
salad every day for example, I don't think it's a bad idea to have a salad
spinner, when you can "easily" rinse and drain by hand.

------
throw0101a
_Begin Japanology_ has an episode on rice cookers (of course):

* [https://www.youtube.com/watch?v=teCnG2ZVAxU](https://www.youtube.com/watch?v=teCnG2ZVAxU)

* [https://www.youtube.com/watch?v=I00uy0ssPP0](https://www.youtube.com/watch?v=I00uy0ssPP0)

[ _Hello, I 'm Peter Barakan._]

------
karmakaze
As mentioned in other comments. The 'keep warm' function is also key. It
allows for having cooked rice 24x7 and is as important a feature as the auto-
shutoff cooker for a daily consumption household.

------
konfusinomicon
Try making black garlic in one. Just do it outside if you can

------
Kiro
I just use boil-in-bag. Can't taste the difference from rice done in a rice
cooker.

------
inakarmacoma
What about the size of the hand being used?

~~~
samus
Finger length doesn't vary that strongly as the palm size. Any actual
differences in output because of millimeters difference in water level could
also due to eyeballing it in the first place.

------
odomojuli
I grew up cooking rice on the stove. My mother preferred it this way because
she liked crisping the bottom. It's definitely an art. Even picking what kind
of rice you want is an art. Even slight variations in your technique can yield
wildly different results. How much you rinse the rice changes the gluten
content and stickiness, how long you let it soak changes the texture and size.
Things like water quality, pot material and heat source make a big difference
for smaller amounts.

Being a minute late is too much sometimes. I used to have to "learn" how to
cook a new bag because the grains are different sizes, sometimes it's not
really brown or white but white-brown or brown-white. The best Japanese rice
is in my opinion, from California. I like Koda Farms, their brown rice is just
about as close as you can get to the flavor of white rice while having a
decent amount of nutrition. Fun fact, the "flower name" for America is 米国.
Means rice country. Nowadays people just say Amerika in Katakana which
technically has a kanji representation as 亜米利加 but even that has the word rice
in it. China calls us 美利坚合众国, which means beautiful country.

It's not difficult to eyeball what it takes to make good rice. Quick and dirty
rule is having just enough water to cover the rice. I just stick my pinky in
and measure up to the second phalange. You basically just heat until it boils,
quickly escape the air, release to mid heat and then keep an eye on it for
about 10-15 minutes without opening the lid. If your technique is good, you
can kind of estimate how long it takes on a linear scale for cups to cooking
time. A clear lid helps, it'll just look right. Key thing to do is take your
rice spatula and just carve out the edges when it's done so you're getting a
more consistent mix.

Later in life, I got the 1.8L Neuro Fuzzy Rice Cooker by Zojirushi. I fell in
love with the name, which is apparently from artificial intelligence. Not sure
how they come up with that.

Here's the thing: sure, it's easy to make one kind of rice and costs almost
nothing to do. With a dedicated rice cooker though, I can make any kind of
rice, in any amount, without having to think about it. The inside of the pot
has markers for your rice quantity and water volume for each type. I have the
larger cooker, so it kind of takes longer (it consistently takes one hour to
cook about 3-4 cups, which is simple to plan around). There's a quick cook
setting which makes no discernible difference in consistency. Every time I
turn it on, it sings a cute little song and then sings another one when it's
done. I find it utterly delightful.

Here's why you get a rice cooker. Sure, you can make rice in like 15 minutes
on the stove. But then what do you do if you have leftovers? Put them in the
fridge where it gets stale? With a rice cooker, I make 5-6 cups at the
beginning of the week, and I can leave it there for at least 72 hours and it
stays incredibly fresh. I wouldn't recommend it, but I've left it in there for
4 days. Constant heat kills any bacteria or mold that might take.

I don't have to worry about my rice technique. I don't have to worry about
storing and heating leftovers. I can make as much rice as I want and save
myself time and effort throughout the week. If I wanted to be even more
efficient, I could let the rice soak overnight, and set a timer for it to
start cooking right before I wake up. It's one less thing to worry about, and
I can time all of my meals around it so that everything's ready at the same
time.

You can also make other things besides rice such as pancakes or pasta in it.
Pasta's a bit more difficult, but I've made perfect pancakes in this thing.

Highly recommend Zojirushi for their excellent insulation products.

~~~
tmd83
72 hours? Doesn't it get dry. My brother bought a cheap Cuckoo one (isn't
available in country) that can keep it for 12 hours I guess but it starts to
dry up after a few. Not sure if it will be germ free for longer but not really
edible. Is that a capability of high end cooker or there's some more secret to
it?

~~~
ubercow13
They have a rubber seal that is supposed to keep all the moisture in. I still
find it dries out or goes yellow after a while though.

~~~
odomojuli
Yeah I've used cheaper rice cookers and the main complaint is they don't
insulate or seal properly. Mine was like $50 and made okay rice but it dries
out almost immediately.

------
ngcc_hk
To this days national rice cooker is still confuse me. Is it Panasonic?

------
graycat
Deleted.

Mod, fix this attack on me.

~~~
jagged-chisel
So measure water and rice, monitor boiling status, modify cooking
temperature...

Yep, needs more automation and less human thought. We need single-serving-
sized pouches of rice, and single-serving-sized bottles of water. Feeding four
people? Use four packets and four bottles. The cooking device can monitor its
own temperature and sing a ditty when it’s done.

~~~
claudeganon
Zoujirushi rice cookers already sing you a song when they’ve finished cooking:

[https://m.youtube.com/watch?v=CMN0jAENzIg](https://m.youtube.com/watch?v=CMN0jAENzIg)

