
The Physics of Fried Rice - cdepman
https://arstechnica.com/science/2020/02/georgia-tech-physicists-unlock-the-secret-to-perfect-wok-tossed-fried-rice/
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ilamont
_The mathematical model Hu and Ko developed isn 't just a fun curiosity; it
should also prove useful for industrial robotic designs._

I recall seeing somewhere (maybe coverage of CES or another trade show) of
automated machines for cooking Chinese dishes that traditionally had to be
made by hand. I can't remember if it was for home or industrial use, and I
don't remember if fried rice was one of the options.

Fried rice _is_ one of the hardest Chinese dishes to cook at home, especially
if you don't have a high-temperature gas range and want to reduce the amount
of oil in the recipe. Lots of scraping and hard pushing motions to break up
the rice, not to mention the slicing/dicing required for prep.

ETA: Found some articles and clips about the tech:

[https://www.scmp.com/tech/innovation/article/1808963/worlds-...](https://www.scmp.com/tech/innovation/article/1808963/worlds-
first-robot-kitchen-cooks-visitors-ces-asia-shanghai)

[http://www.chinadaily.com.cn/a/201805/17/WS5afd263fa3103f686...](http://www.chinadaily.com.cn/a/201805/17/WS5afd263fa3103f6866ee9050.html)

[https://www.digitaltrends.com/home/robot-cooking-
machine/](https://www.digitaltrends.com/home/robot-cooking-machine/)

~~~
thaumasiotes
> Fried rice is one of the hardest Chinese dishes to cook at home, especially
> if you don't have a high-temperature gas range and want to reduce the amount
> of oil in the recipe. Lots of scraping and hard pushing motions to break up
> the rice, not to mention the slicing/dicing required for prep.

I found this funny. That's a fair call on the slicing/dicing, except I'm
pretty sure the traditional way to make fried rice is to throw in whatever
leftovers you already have to hand.

So if you're already cooking other Chinese food, fried rice is just a mostly-
free leftovers dish. It works as part of the entire Chinese-food cultural
complex; it's harder to slot in to a schedule of foreign food, where every
element of it has to be prepared specially.

(Of course it's popular in restaurants now, and they must make it in a
consistent way. But you don't need to.)

~~~
jjeaff
Doing a mushy, sad fried rice at home is easy. But I think op was referring to
the difficult of making -good- fried rice.

It's not the ingredients or prep that is hard, it's that you need a carbon
steel wok and enough BTUs to keep that wok around 500F even while dropping
cold ingredients into it.

Without a carbon steel or cast iron pan and enough constant temp, you won't
get the "wok hei" which really affects flavor and texture.

J Kenji Lopez has a great write up on the difficulties of good fried rice at
home. [https://www.seriouseats.com/2012/06/the-food-lab-for-the-
bes...](https://www.seriouseats.com/2012/06/the-food-lab-for-the-best-stir-
fry-fire-up-the-grill.html)

~~~
grawprog
>was referring to the difficult of making -good- fried rice.

I don't really understand, just fry your ingredients at high heat and don't
stop stirring. Make sure the pan is hot before you add oil, make sure the
oil's hot before you add the ingredients. Start with the meat/protein, when
that's browned, if you really want it all nice and cooked well, take the meat
out and put it aside then do the onions, theb mushrooms, peppers, veggies etc.
Garlic and ginger and stuff last, re-add the meat, add your cooked rice, maybe
an egg at that point and keep stirring until it's nice and golden brown.

~~~
kevinlou
Is it common to throw the egg in at the end? I was always taught to fry and
scramble the egg in the oil first.

~~~
askvictor
There seem to be a few schools of thought - one is to mix some egg through the
cold rice before frying, one is to add egg mixture near the end, one is to fry
the egg and like an omelette and chop it up and add.

~~~
thaumasiotes
> one is to fry the egg like an omelette and chop it up and add

That's the one I would consider normal.

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0xff00ffee
Oh god this brings back traumatic memories: When I was getting my degree in
culinary arts at Bristol (Boston, MA) in the mid-80's I had "Professor Wong",
not a professor but a chef who taught a segment on Chinese cuisine. I had to
make ~5lbs of fried rice every day for two weeks and he would say in a thick
over-emphasized (phony) chinese accent, "You burn rice, you fail!" every day
-- with a big smile, of course, but meaning it. And holy HELL was I sore every
day during that period. The industrial woks are very heavy and you do need to
keep it in constant motion.

~~~
pcurve
Lol what a delightful story :)

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thaumasiotes
Huh. This whole thing appears to be about how the motion of the wok affects
the fried rice.

But at the only restaurant I've watched fried rice prepared at (a college
cafeteria in Shanghai), it was done on a flat iron surface, teppanyaki-style.
And that was considered the good cafeteria.

"The physics of fried rice" seems to overestimate the scope of the study a
bit.

~~~
asutekku
I think “cafeteria” is the key word in here. They most likely do not have the
time & resources to do it how they would do it in a high end restaurant.

~~~
thaumasiotes
That makes no sense; iron cooking counters everywhere and different chefs at
different stands to prepare your food on demand are a much _bigger_ investment
of time and resources than preparing food in bulk in the back on a single
stove/counter.

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zbaylin
Happy to see my school getting mentioned on HN. Dr. Hu has a TEDx talk called
"Confessions of a Wasteful Scientist"
([https://www.ted.com/talks/david_hu_confessions_of_a_wasteful...](https://www.ted.com/talks/david_hu_confessions_of_a_wasteful_scientist))
that talks a bit more about research he has done in this vein.

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bfung
Grandpa bfung said (paraphrased from translated Cantonese): “if your fried
rice is the color of soy sauce, you’re doing it wrong - that’s the color of
poop”.

Just wanted to share some fried rice wisdom.

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Apofis
All of a sudden I got super excited and wanted to go buy a wok, something I've
wanted to do for a while, even started looking on Target... then I realized I
have an electric range.

I could get an outdoor propane stove, can't wait for it to get warmer.

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Magi604
Chicken Fried Rice used to be my favorite go-to Chinese restaurant dish, but
too many places loaded up the dish with tons of rice and veggies and skimped
hard on the chicken, presumably to save on meat costs.

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s_ngularity
You should try a Vietnamese place if there’s one near by you. The ones around
here at least don’t seem to skimp on the meat as much

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thedance
The comments of this article are where the meat lies. There’s no way anyone is
flipping rice in a 1200-degree steel wok.

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bilekas
When physics and food meet.. It's a dinner made in geometrical heaven, and
shoulder pain evidently.

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rzmnzm
I usually cheat and use parboiled rice, it won't become a sad mush.

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ruffyen
Why in the hell is this considered...technical?

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wnevets
If it is not, why would it matter? Hacker news always has non technical post
on its front page.

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ruffyen
While that may be true this is a new level information i dont care about...

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jlisam13
then don't read it

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jvagner
...and if you can't _stand_ to see it, "hide" it.

