Rice Cookers
Understanding Some of the Global and
Societal Differences of Rice Cooking
Initially prepared by: Kang Kang
M.S. Student, Industrial Engineering
Penn State University
Spring 2011
Introduction



Rice is the seed of the monocot plant: Oryza sativa
One of the oldest foods – traced to 5000 BC by archaeologists
It is the most important staple food for a large part of the world‘s
human population, especially in East and South Asia, the Middle
East, Latin America, and the West Indies [1]
[1]

[2]
[3]
When rice is harvested, it has a inedible husk (hull) that surrounds
the kernel, which is removed along with the stalk and other foreign
material using a variety of specialized equipment in a rice mill
Grain Sizes
Rice is divided into three types based on seed size
Long Grain
Medium Grain
Short Grain
Cooked grains are
separate, firm and fluffy
Cooked grains are moist,
tender and tend to cling
together
Cooked grains are
moister, more tender, and
tend to cling together
• As a rule, the shorter the grain, the more tender the rice is, and
the more it clings together
Types of Rice

Forms of Rice
• Brown rice: All rice is originally brown. Brown rice (as you buy it) is
rice from which only the hull has been removed. When cooked, it has a
slightly chewy texture and a nutlike flavor. In different countries brown
rice has different names - Chinese: 糙米; pinyin: cāomǐ; literally "rough
rice"; Korean: 현미; hyeonmi; Japanese: 玄米; genmai; Thai: ข้ าวกล้ อง;
Vietnamese: gạo lứt. [2]
• Regular milled rice (White rice): Has been completely
milled and polished, removing the bran layer.
Brown rice [4]
White rice [5]
Types of Rice

Forms of Rice
• Parboiled rice: Most commonly used in European and American
cooking. The grains do not stick together giving it a 'fluffy' texture that
American/UK cookbooks find desirable. The parboiled rice is soaked,
steamed, and dried before milling. This way nutrients stay within the
grain, and the surface starch is reduced, producing cooked rice that is
somewhat more firm in texture and separate when cooked.
• Unmilled rice: Before polished rice was introduced, people ate
unmilled rice, which was a little bit harder than polished rice. Many
people still cook and eat unmilled rice.
Parboiled Rice [6]
Unmilled rice to milled rice [7] (From right to left)
Types of Rice
Rice Varieties
 There are more than 40,000 different varieties of
rice worldwide. Two common and popular varieties:
•
Basmati rice: It has the longest grain of
all and a translucent appearance. It also has
a distinctive sort of spicy aroma, which
matches spicy dishes perfectly.
•
Jasmine Rice: Sometimes known as
Thai fragrant rice, it is a long-grain variety of
rice that has a nutty aroma, The grains will
cling when cooked, though it is less sticky
than other rice.
[8]
Jasmine rice [9]
Cultural Differences
Due to cultural differences, the way people eat, prepare and serve rice are
very different:
 Differences in types of rice
 Differences in how rice is cooked
[11]

[12]
[13]
[14]
Differences in taste and consistency of rice
Sticky and glutinous [15]
Medium stickiness and non-glutinous [16]
Non-sticky and separate
grains [17]
World Map Of Rice Cultivation
Korea
Japan
India
China
Thailand
Source: http://www.ricemap.org/tutorial/
China

Traditional Chinese ways of cooking rice
[18]

[19]
[20]
Rice varieties in China
Indica rice is dominant in the south (long-grain, medium
stickiness), while japonica rice is widely planted in the
north (short-grain, more sticky)
China

Different Needs
•
•
•
•
Side dish
Stir fried rice
…
Rice porridge/congee
[21]
[22]
Map
Japan
Japonica Rice or ‘Sushi Rice’
Also called uruchi-mai, it is a medium-grain rice, which
is used for almost any kind of Japanese dish, including
sushi and onigiri
[23]
[24]
Japan
Sushi
Traditional sushi rice is made from short-grained, white
rice (preferably Japanese rice), and it is mixed with salt,
sugar, sake and vinegar to make the rice fluffy and
sticky (though there are many ways to make sushi rice)
[25]
[26]
[27]
Map
Korea
Korean Rice
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

Korean rice is short grain rice like “sushi rice” and has a
lot more starch than long grain rice because it is highly
glutinous
Unlike rice from Southeast Asia or North America,
Korean rice is moist and sticks together rather than
falling apart
This makes it easy to eat
with chopsticks
[28]
Korea

Different Needs
Bibimbap [29]
Purple Rice [30]
Beany rice [31]
Map
Thailand
Thai Fried Rice
In Thailand, fried rice is often served with cucumber and a wedge
of lime. The unique taste of the Thai rice comes from a mix of fish
sauce, soy sauce, chili peppers and lime. The rice is decorated
with cilantro and a dusting of freshly ground pepper. When you
make fried rice it is good to use a little dry rice (normally Jasmine
Rice) so that the rice does not stick – this is an important
requirement of fried rice
[32]
Map
India
Rice Varieties
Rice is the staple food of all Indians. Different regions of
India eat different varieties of rice and cooking methods.
[33]
[34]
India
Different cooking methods and taste preference
The preferred consistency is non-sticky and separate
grains, which is very different from Chinese/Korean rice.
There are several ways to prevent the rice from sticking
(e.g., adding extra oil or ghee, or draining the rice and
pouring room temperature water on top of the grains
after they are cooked through to flush and drain any
remaining starch). Spices can also be added before
cooking the rice or after steaming it.
[35]
[36]
Other Countries
Middle East:
• Rice is a common side dish
• Many dishes are served over rice
• Normally, rice is fried first and
should be non-sticky
[37]
Brazil:
• Overwhelming majority of the population
eats rice and beans every day of their lives
- core of Brazilian cuisine and of Brazilian nutrition
• Rice and beans play a large part in the cuisines of many
other parts of Latin America (Cuba, Venezuela, Mexico),
but rice cookers are not often used in those regions
[38]
United States
Instant Rice:
• Pre-cooked rice that is dehydrated and
repackaged
• Dehydration removes a lot of its flavor
[39]
How to Cook Rice
Cook rice in the pot
• Typically rinse rice first, then put two cups
of water to one cup of rice in the pot, boil
water, heat and stir during the process
• Different rice types and amounts require
different amounts of water
• Can easily be over-cooked or unevenly
cooked – need to monitor while cooking
[40]
Poorly Cooked Rice

Over-cooked/burned rice:
[42]

Too much water added:
[43]
How to Cook Rice
Cook rice in the pot
• Typically rinse rice first, then put two cups
of water to one cup of rice in the pot, boil
water, heat and stir during the process
• Different rice types and amounts require
different amounts of water
• Can easily be over-cooked or unevenly
cooked – need to monitor while cooking
[40]
Use a rice cooker
• Much easier, one-bottom, and different
functions to choose
• No need to stir/monitor during cooking
• No concern of over-cooking
[41]
General Operation
How does a rice cooker know the rice is ready?

A heating device inside the container begins to heat up the
water to its boiling point, which is 212° F (100° C).

As the water boils, the rice absorbs the steam, and some of
the steam escapes through the lid.

When the water is nearly all gone, the temperature of the food
will begin to rise above 212° F (about 105° C).

This change in temperature is monitored by a sensor hidden
in the bottom of the rice cooker, which triggers a switch to turn
the cooker off or lower the temperature to keep rice warm
Rice Cooker Design

Structure
• Pot style
• Separate pots
• Cool touch

Operation System
Aroma ARC-773-1G
Aroma ARC-883TC
Panasonic SR-G06FG
Aroma ARC-914SBB
• Mechanical
• Electronic
• Micro-computer control

Cooking principle
• Pressure cook
• Heating
Panasonic HD4761
Rice Cooker Features
Inner Pan
Essential for cooking, should be non-sticky and evenly conducting heat
Good
• Single coat of non-sticky material
Panasonic HD4761
Better
• Several layers of coding: non-sticky layer, aluminum alloy, hard anodic
oxidation coating
Best
• Vacuum insulated pan to ensure even heating
• Innovative coating materials such as copper-coded, morion-coded
(crystal-coded), whole casserole material (argil material)
Rice Cooker Features

Cooking options
Single touch
Single option
Panasonic SR-G06FG
Menu with indicator light Various rice
Aroma ARC-150SB
Toshiba RC-10MY
Delay timer
options: brown
rice, white rice
Various rice and
cooking options:
porridge, soup,
cake, slow cook
LED menu
Keeps rice
warm automatically
Reheating
element;
keeps rice
warm for a
long time
Cooking Control Technologies
Control Technologies
• Variable Pressure Control
• Computerized temperature control
Fuzzy Logic (Sensor Logic or Smart Logic)
• Adjusts the amount of heat based on the amount of water, and the amount
of heat absorbed by the food
• Rectifies any mistakes in water measurements or other human errors by
adjusting the cooking time and temperature to cook rice to perfection
Induction Heating [3]
• Rather than heating the inner pot in a traditional manner, induction-heating
uses electromagnetic energy to heat a separate copper-coated inner pot
• The heat and moisture penetrate deeply and evenly into individual rice
grains to produce sweet and fluffy rice
• Technology widely used in Japanese rice cookers and is usually powered
by a micro-computerized control and combined with pressure control
technology
Low-End vs. High-End Cookers

San Jiao Rice Cooker
Features:

Automatically keep warm
Price: $9

Zojirushi NP-LS

Features:



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
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Multi-functional
IH technology
LCD controller
A mini pump that pumps outside air into the cooker to add pressure
Programmable melody or beep on/off indicator
Price: $1000
References
[1] http://toddyhotpants.com/blog/2009/02/23/motorbike-trip-ha-nội-sai-gon/
[2] http://news.sciencemag.org/sciencenow/2010/05/genetic-discovery-promises-to-bo.html
[3] http://www.buzzle.com/articles/types-of-rice.html
[4] http://www.healthcaretipsandguides.com/some-health-benefits-of-brown-rice.html
[5] http://mycoloredlinks.com/goodBlogs/archives/583
[6] http://www.sakayanyc.com/about_classification.php
[7] http://www.marcotec.com/onepass.htm
[8] http://www.google.com/imgres?imgurl=http://www.fotobank.ru/img/
[9] http://www.realsimple.com/food-recipes/browse-all-recipes/perfect-jasmine-rice
[10] http://www.sushiencyclopedia.com/how_to_make_sushi/how_to_cook_rice_with_a_pot.html
[11] http://www.cafenilson.com/2009/11/daring-cooks-sushi/
[12] http://www.babyhome.com.tw/mboard.php?op=d&sID=2702555&bid=13&r=128&page=1
[13] http://www.smallkitchenappliancestore.com/
[14] http://www.diytrade.com/china/4/products/5266417/microcomputer_rice_cooker.html
[15] http://concasse.blogspot.com/2009/03/laotiannorthern-thailand-meal-isaan.html
[16] http://inhabitat.com/sticky-rice-is-1500-year-old-secret-to-super-strong-chinese-buildings/
[17] http://qwickstep.com/search/tamarind-rice.html
[18] http://www.flickr.com/photos/fennifer1390/3509651616/
[19] http://www.flickr.com/photos/fennifer1390/3508840861/in/photostream/
[20] http://www.cafenilson.com/2009/11/daring-cooks-sushi/
[21] http://www.homemade-chinese-soups.com/congee.html
[22] http://khatiya-korner.com/blog/2009/06/12/congee-rice-porridge/
[23] http://www.realsimple.com/food-recipes/browse-all-recipes/
[24] http://www.ifood.tv/recipe/japanese_sushi_rice
[25] http://www.cafenilson.com/2009/11/daring-cooks-sushi/
References
[26] http://www.deliciousmagazine.co.uk/articles/how-to-make-sushi
[27] http://exurbanpedestrian.wordpress.com/2010/01/10/ahhhh-sushi/
[28] http://www.wonderfulworldofdave.com/2010/05/korean-tofu-house-cerritos-ca.html
[29] http://www.dineouthere.com/restaurants/category/robson
[30] http://foreignerjoy.blogspot.com/2010/08/foreign-rice-hunting-and-tasting-taco.html
[31] http://foreignerjoy.blogspot.com/2010/08/foreign-rice-hunting-and-tasting-taco.html
[32] http://islam4parents.com/2009/01/thai-fried-rice/
[33] http://www.nelmani.com/indian-rice.htm
[34] http://beyondwonderful.com/recipes/sidedishes/beansgrains/basmati_rice.htm
[35] http://www.texasoysters.org/ricerecipe.html
[36] http://www.wizardrecipes.com/blog/rice-cooking-techniques.html
[37] http://www.ifood.tv/network/middle_east_rice
[38] http://simplyrecipes.com/recipes/red_beans_and_rice/
[39] http://www.theteacherscorner.net/forums/showthread.php?t=4954
[40] http://www.mare.ee/indrek/sushi/
[41] http://www.smallkitchenappliancestore.com/
[42] http://lifehackery.com/2008/05/17/50-amazingly-helpful-time-tested-tips-for-the-kitchen/
[43] http://foodwisenutrition.blogspot.com/2010_09_01_archive.html