「白米急速」ってどうやって？

August 17, 2006 8:46 PM

How on earth does the "high speed white rice" setting on a rice cooker work? I know the basics of rice-cookery (thermostat attached to heating element checks for the presence of liquid water, as evidenced by temperature staying at the boiling point) but I have no idea how it manages to optionally cook short-grain white rice in half the time it usually takes.
posted by DoctorFedora to Food & Drink (12 answers total)

pressure cooker?
posted by sindas at 8:59 PM on August 17, 2006

Response by poster: That's the thing -- it doesn't seem to have any means of producing pressure, other than the fact that the vent hole isn't all that big.
posted by DoctorFedora at 9:01 PM on August 17, 2006

More heat coupled with constant agitation, so that the rice on the bottom does not get burned?
posted by |n$eCur3 at 9:13 PM on August 17, 2006

I don't know the answer to this, but I always assumed that since it only takes about 30 minutes or less to cook rice on the stovetop using a "donabe" (not counting the soaking time), the high speed setting on an electric rice cooker is the actual minimum time it takes to cook the rice, and the usual setting just takes longer because of, say, the extra "murashi" (steaming?) and such waiting time. (On a stove, you only have to heat the donabe on high until it comes to a boil, then on low heat for about five minutes. Then you turn the gas off and just let it sit there.)

I'm interested in the answer to this!
posted by misozaki at 9:23 PM on August 17, 2006

It pretty much just cooks at a higher temperature, which makes it slightly harder on the outside, which is why the normal setting cooks as slowly as it does. On the high-end induction cookers this shouldn't cause any burning since the cooking method prevents this in the first place.

Think roasting a pig at 1000F for 20 minutes vs. 200F for 100 minutes..
posted by kcm at 9:27 PM on August 17, 2006

It pretty much just cooks at a higher temperature

Well, no, it is limited to cooking at the boiling point of water unless there is a pressure lid -- which DoctorFedera has indicated is not the case.

Are you supposed to add more water for the high-speed setting? I know nothing about this rice cooker but I seem to recall that rice cooks faster if boiled rather than steamed, so perhaps the high-speed setting applies more heat to boil more water in which the rice remains fully immersed for most of the cooking time.
posted by randomstriker at 10:09 PM on August 17, 2006

randomstriker: Dunno about DoctorFedora's cooker, but my own cooker uses the same amount of water for regular speed and for high speed cooking.

Misozaki's guess seems to make the most sense: You can cook rice by heating the water it's in to boiling temperature for, let's say, X minutes, and then letting it sit in the steam for 4X minutes, for a total time of 5X minutes, or you can boil the water for, let's say, 2X minutes, then let it steam for 2X minutes, for a total time of 4X minutes. By increasing the amount of boiling time, and decreasing the amount of steaming time to a greater degree, you can cut down on the cooking time. That seems like the most likely way that it works.
posted by Bugbread at 10:49 PM on August 17, 2006

This is a cool question. I went out searching, and I couldn't find anything definitive, but it seems to do with heat. It looks like it depends on how hot the rice can get, and how quickly. There are pages like this one and this one that suggest the key is greater heat. One of these pages boasts "This takes advantage of the strength of a gas flame with a special high thermal conductivity pot, for speedier rice cooking."

I'm amazed how advanced some of the rice cookers I found were.. There were ones with very fine temperature and pressure controls that let you fine tune texture and flavour. Incredible. On this page there is a model that has an inner pot made from a special carbon compound designed to emulate heat from charcoal. Others use ultrasonic waves to break down the coating of the rice and force water deeper into each grain. In case you're interested, the carbon rice cooker sells for more than $550.
posted by mariokrat at 11:15 PM on August 17, 2006

We have a Japanese rice cooker with a regular setting and a speedy setting. The regular setting gives the rice about half an hour to soak before it starts cooking. The speedy setting skips this step and starts cooking immediately. The texture of the rice differs between the two settings, but both are quite edible.
posted by Alison at 4:39 AM on August 18, 2006

Nice post title!
posted by languagehat at 5:30 AM on August 18, 2006

Second what Alison says. That's how the instructions for my Zojirushi explained it. Less soaking. And possibly less steam-sitting after. Also, a helpful anime pixie lives in there if the directions are accurate.
posted by kookoobirdz at 6:40 AM on August 18, 2006

I don't have a rice cooker, but I cook rice (lots!) in a saucepan on the stovetop. It takes about 25 - 30 minutes from the time I turn on the gas. About 5 - 10 minutes to reach a boil, then 20 minutes of simmering. The soaking/steaming method takes a lot longer, so your rice cooker probably just boils the rice on the fast-cook setting, as others have said.
posted by Quietgal at 9:13 AM on August 18, 2006