Speaker 1: Welcome to Brainstuff, a production of iHeartRadio, Hey Brainstuff, Lauren Bolebaum. Here,
Speaker 1: Burned chunks or gooey paste can be the disappointing result
Speaker 1: of rice gone wrong, but with the use of a
Speaker 1: rice cooker, the odds even up for even the glutsiest
Speaker 1: in the kitchen. A rice is the staple grain in
Speaker 1: many cuisines around the world. But before the invention and
Speaker 1: adoption of modern kitchen technology alike electric and gas heating elements,
Speaker 1: cooking rice was a finicky, hours long process that required
Speaker 1: you to stand around over a cast iron pot, making
Speaker 1: adjustments to a coal or wood fire in order to
Speaker 1: get the heat just right during different parts of the
Speaker 1: cooking process. Although simple electric rice cookers go back to
Speaker 1: the nineteen twenties in Japan, the first commercial one for
Speaker 1: home use didn't debut until nineteen fifty six from Tashiba. People,
Speaker 1: and perhaps specifically women who often took on the task
Speaker 1: were Ready. Company records show that just four years later,
Speaker 1: about half of Japanese homes had a rice cooker. These days,
Speaker 1: rice cookers range from basic models that'll run you less
Speaker 1: than thirty bucks to ones with fancy features that cost
Speaker 1: over five hundred and Although they're ostensibly meant for cooking
Speaker 1: you know, rice, they can be very versatile. Some people
Speaker 1: use rice cookers as their primary cooking tool for everything
Speaker 1: from spaghetti to spare ribs to scrambled eggs. So today
Speaker 1: let's talk about the technologies behind rice cookers. Rice needs
Speaker 1: two things to go from hard, shelf stable grains to
Speaker 1: tender morsels, lots of water and lots of heat. You
Speaker 1: generally accomplish this by boiling grains of dried rice in
Speaker 1: water anywhere from equal parts of each to twice as
Speaker 1: much water by volume. The rice is done when all
Speaker 1: of the water has been absorbed and or steamed off,
Speaker 1: and the grains are whatever degree of tender you're looking for.
Speaker 1: It is ideal if you can do this without melting
Speaker 1: a layer of rice into a sticky, burnt mass at
Speaker 1: the bottom of the pot. There are a few ways
Speaker 1: to accomplish this automatically. Most start with an electric heating
Speaker 1: element set into a base which can also hold a
Speaker 1: cooking pot. You add rice and water and cover with
Speaker 1: the lid that came with the appliance. The heating element
Speaker 1: heats the pot, which boils the water. But how does
Speaker 1: it know when it's done. The classic technology, the least expensive.
Speaker 1: The type I've got operates on a simple heat sensitive
Speaker 1: magnetized switch. Okay, you turn on this type of rice
Speaker 1: cooker by pressing down a switch on the outside of
Speaker 1: the unit, and when you do, you'll hear a little clock.
Speaker 1: That's because the switch is connected to a lever that
Speaker 1: brings two surfaces in contact with each other that are
Speaker 1: electrically conducive. This completes an electrical circuit and powers the
Speaker 1: heating element. The circuit stays closed because the two surfaces
Speaker 1: are magnetic, but one surface, the upper surface of the pair,
Speaker 1: is made of a material that's only magnetic up to
Speaker 1: about one hundred and two degrees celsius, which is right
Speaker 1: above the boiling point of water. This is a very
Speaker 1: clever bit of physics. Water boils at one hundred degrees
Speaker 1: celsius and won't get hotter than that at normal Earth pressure.
Speaker 1: So as long as there's water in the pot as
Speaker 1: the rice is cooking, the temperature at the bottom of
Speaker 1: the pot will hold steady. At one hundred the temperature
Speaker 1: is in check thanks to the presence of water, but
Speaker 1: when it's all absorbed and or boiled off, the heating
Speaker 1: element can get to work on the pot and or
Speaker 1: the rice itself, which can get considerably hotter than one
Speaker 1: hundred degrees at normal Earth pressure, so the temperature at
Speaker 1: the bottom of the pan leaps up, at which point
Speaker 1: our temperature sensitive magnet stops being magnetic and drops the
Speaker 1: other half of the pair, breaking the circuit and turning
Speaker 1: the heating element off with another little clunk. Except in
Speaker 1: a lot of rice cookers like this, the heating element
Speaker 1: doesn't turn all the way off, but rather switches to
Speaker 1: a warming function. This works thanks to another type of
Speaker 1: heat sensitive switch called a bimetal switch. A bimetal switch
Speaker 1: is a type of switch that's made up of two
Speaker 1: types of metals sandwiched together. Makes sense, right. Each of
Speaker 1: the two is chosen because they are bendable and because
Speaker 1: they expand at different rates when exposed to heat. So
Speaker 1: the switch starts out flat but will bend one way
Speaker 1: or the other at different temperatures because the metals are
Speaker 1: expanding or shrinking at different rates, and you can use
Speaker 1: this property to connect and disconnect a circuit at different temperatures.
Speaker 1: In the case of our rice cooker, at around sixty
Speaker 1: degrees ce elius, that's one forty fahrenheit fairly cool. The
Speaker 1: switch bends and connects the circuit, turning the heating element
Speaker 1: on a butt at around eighty celsius or one hundred
Speaker 1: and seventy five fahrenheit fairly hot. The switch bends the
Speaker 1: other way, breaking the circuit and turning the element off.
Speaker 1: It will keep toggling, holding the temperature of the pot
Speaker 1: nice and warm until you unplug the unit. But of
Speaker 1: course we humans are not confined to manual physical switches anymore.
Speaker 1: Digital rice cookers contain digital thermometers connected to a simple
Speaker 1: computer that can be programmed at the touch of a
Speaker 1: few buttons on the outside of the unit to heat
Speaker 1: or warm the pot, two particular temperature settings, four particular
Speaker 1: lengths of time, like the way that we use standard microwaves.
Speaker 1: Computer controlled rice cookers were first introduced in nineteen seventy nine.
Speaker 1: But if you are going to go ahead and put
Speaker 1: a computer into a rice cooker, why not ask it
Speaker 1: to do a bit more work for you. Rice cookers
Speaker 1: were one of the first home appliances to make use
Speaker 1: of the theory of fuzzy logic, which was developed by
Speaker 1: computer scientists in the nineteen seventies and now helps everything
Speaker 1: from washing machines to refrigerators to subway cars function. Fuzzy
Speaker 1: logic is sort of what it sounds like, logic with variables.
Speaker 1: Digital devices operate on boolean logic, which means ones in
Speaker 1: zeros you know on or off, yes or no. Fuzzy
Speaker 1: logic opens up the field of answers to all of
Speaker 1: the numbers in between one and zero. Devices programmed with
Speaker 1: it can recognize an almost yes versus a slightly yes
Speaker 1: and act accordingly. This lets you program algorithms that take
Speaker 1: variables into consideration, like not just is the pot hot,
Speaker 1: but is it getting hotter quickly, and then make a
Speaker 1: decision about how to control the temperature based on that.
Speaker 1: Idea is that these machines can adjust for the actual
Speaker 1: circumstances occurring in real time. Maybe the ambient pressure is
Speaker 1: making the cooking go faster, or you added too much water,
Speaker 1: and it can cook the rice perfectly regardless. It's way
Speaker 1: better than just using on off temperature settings, and probably
Speaker 1: better than any adjustments a hungry and impatient human might make.
Speaker 1: While fuzzy logic rice cookers function under the same premise
Speaker 1: as basic models, their mathematical programming can deliver a slew
Speaker 1: of customized cooking options, making precise fluctuations in cooking time
Speaker 1: and temperature depending on the programs selected. These may include
Speaker 1: settings for white rice of varying textures, sushi rice, jasmine rice,
Speaker 1: brown rice, germinated brown rice, mixed rices, knge steel cutoats,
Speaker 1: rapid cooking, extended warming, and reheating. And that's just the beginning.
Speaker 1: Some machines have settings for steaming foods, baking cakes, auto cleaning,
Speaker 1: and delayed timers, so you can preset the machine to
Speaker 1: start cooking at a particular time. Oh and if you
Speaker 1: do want a layer of crisp, golden brown rice at
Speaker 1: the bottom of your pot for dishes like tadig, there
Speaker 1: are rice cookers for that too. You add a bit
Speaker 1: of vegetable oil to the pot, and after the main
Speaker 1: cooking is done, a timer holds the pot to the
Speaker 1: heat long enough to crispit. There are also rice cookers
Speaker 1: out there that don't use a standard electric heating element.
Speaker 1: These days, you can find models that use induction heating technology,
Speaker 1: which I could have sworn had already done an episode about,
Speaker 1: but I have not, and I'll have to rectify that
Speaker 1: in the future. Very basically, induction cookers don't waste energy
Speaker 1: heating an element that then heats a pan, but rather
Speaker 1: use magnetic fields to heat the pan directly. There are
Speaker 1: also pressure rice cookers, which seal and pressurize their contents
Speaker 1: to allow for faster cooking times and hotter temperatures. Pressure
Speaker 1: cooking also a whole different episode. Whatever kind of rice
Speaker 1: cooker you're using, there are all kinds of recipes out
Speaker 1: there for how to get the most out of it.
Speaker 1: When it comes to rice and beyond, at a certain point,
Speaker 1: it's a hot pad with a fitted pot. Anything you
Speaker 1: want to warm or cook, especially anything involving a lot
Speaker 1: of liquid, can be done in a rice cooker with
Speaker 1: enough tenacity a rice cooker. Poached fruit, hard boiled eggs,
Speaker 1: homemade soups, whatever you're cooking in it. Take a moment
Speaker 1: to appreciate your humble or not so humble rice cooker,
Speaker 1: and if you don't have one, consider picking up a
Speaker 1: basic model. After all, it's a robot that, if it
Speaker 1: could want things, would want you to eat good rice.
Speaker 1: That's a good robot to have around. Today's episode is
Speaker 1: based on the article how rice cookers work on HowStuffWorks
Speaker 1: dot com, written by Jessica Tooothman for more about the
Speaker 1: history of rice cookers. Check out my other podcast Savor
Speaker 1: for the Warm and Fuzzy rice Cooker episode. Brainstuff is
Speaker 1: production by Heart Radio in partnership with how stuffworks dot
Speaker 1: com and is produced by Tyler Klang. But four more
Speaker 1: podcasts from iHeartRadio. Visit the iHeartRadio app, Apple Podcasts, or
Speaker 1: wherever you listen to your favorite shows.