How an automatic rice cooker works

[lizard-of-oz]

Argh. I watched it. Are you happy now?

Edit: At double speed with CCs on!

[anon3072533]

@Michael_Black

Though, cooking basmati rice with coconut milk was a problem, if I recall properly. I can’t remember details. I used a can of coconut milk and then water to make the total liquud but it seemed to fool the mechanism that normally knew when the rice was cooked.

Hmm, from a quick google it appears that coconut milk is only about 50% water (the rest would be pureed coconut flesh and fat, and maybe some guar gum added as a stabilizer) so it seems if you’re using a can of coconut milk plus water to make up the amount of liquid called for, you might want to add an additional half-can of water, in order to have enough actual water to cook the rice?

(Note, guar gum can do weird things, including burn easily—I once ruined a batch of chocolate toffee, by not realizing that the whipping cream that I had bought was not 100% pure cream but had some guar gum added to it (curses). The toffee just seized up (sort of like curdling) in the pot and burned. Not saying that would happen with cooking rice and coconut milk with guar gum, but might be something to watch out for.)

[gadgetphile]

@Ryuthrowsstuff

A similar explanation?

Pressure cookers need not detect anything, they use a valve that opens when they hit a given psi. And a gasket that lets air out, that locks when the pressure gets high enough. It’s all mechanical.

…

And its just valves and gaskets. That’s why you can have a completely analog pressure cooker you stick on a burner.

The electric ones do it the same, and they don’t really need to detect anything. The pressures and temps are fixed. Which pressure level is programmed in for preset/programmed functions. At most they might need to know if the valve tripped so they can toggle the heat and off to maintain pressure without boiling off too much liquid. But you could do that with a simple switch.

Thanks for mansplaining about how pressure cooking works, but really, yes, an electric pressure cooker has to detect something. Just as with a manual pressure cooker, it needs to detect when it has reached some critical point where it can lower the heat, otherwise you’d blow off the safety valve since the pressure regulator cannot bleed it off as fast as the water inside can be boiled off at a high heat setting. And no pressure cooker is going to operate at only a low heat setting since that would take forever to come up to pressure.

So, I guess you’re right, all it needs is a simple switch, but it also needs something to say when to throw that switch. That’s the whole sensing mechanism.

If you have ever used something like an Instant Pot, you would know that it doesn’t even bleed off excess pressure as it cooks. It rapidly comes up to “pressure” and then automatically lowers the heat so it doesn’t go over enough to vent.

Okay, it’s not an exciting video, but to answer my first post, here is how an electric pressure cooker works.

I was wrong in assuming there wasn’t any actual pressure sensor: I had figured that if one assumes there is actually water in it, then all you’d need is a thermometer, since pressure would just be a function of temperature. Even altitude wouldn’t be a factor since it’s absolute pressure. If there weren’t water in it, usually the pressure would be lower for a given temperature, so it wouldn’t be an explosion hazard. Now, if you filled it with dry ice, or anything else with a higher vapor pressure than water, then if you’re lucky, the safety would blow off. But since there is actually a pressure sensor, my whole argument is moot.

[Wanderfound]

@LutherBlisset

seeing psi used in 2020 gives me the willies

PSY- Gangnam Style (Official Music Video)

[LutherBlisset]

Ow gawd. Why are ye doin dis? Shtooop!

[FGD135]