• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.234-240
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• 1998

This study attempted to determine the effect of various thawing methods and storage periods on the quality of froen cooked rice. Frozen cooked rice was thawed at four different methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature after 10 days, 30days and 90 days frozen storage. We conducted a physico-chemical analysis (moisture content, dehydration rates, degree of gelatinization, color value and texture) and sensory evalution on the frozen-thawed cooked rice. The study showed that there were no significant differences on the quality characteristics of frozen-thawed cooked rice during the storage period of 90 days. However, the thawing method of pressure cooking caused high moisture content, rapid dehydration rates, and a high degree of gelatinization on the cooked rice. Thus, the desirabililty for the rice diminished becaused of the excess moisture content and the change of appearance and testure in the rice due to the high temperature. There were similiar quality characteristics to the cooked rice after forzen-thawing whether by conventional cooking or by microwave heating and just after cooking. Thawing at room temperature also caused a significant decrease in quality characteristics.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.705-709
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• 1997

Changes in retrogradation degree of nonwaxy milled rice cooked at different pressure and stored in electric rice cooker at $74^{\circ}C$ were investigated. The moisture contents of nonwaxy milled rice cooked at $1.0{\sim}1.9\;atm\;and\;1.2{\sim}1.5$ water/rice ratio were $59.9{\sim}64.3%$. When nonwaxy milled rice was cooked at high pressure, X-ray diffraction patterns of cooked rice exhibited the V-type having nearly no crystallinity. Retrogradation peak of cooked rice from DSC thermogram was observed in the temperature range of $41.9{\sim}62.4^{\circ}C$ and was not appeared in cooked rice above 1.5 atm. During storage at cooker for 24 hr, retrogradation enthalpy of cooked rice was increased and retrogradation peak was not appeared above 1.7 atm. In cooking and storage of cooked rice, retrogradation degree measured by ${\alpha}-amylase-iodine$ method in high pressure gelatinized samples was lower than that in low pressure gelatinized ones.

• Korean Journal of Human Ecology
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• v.5 no.1
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• pp.81-88
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• 1996

The effects of water to rice ratio on the properties of cooked nonwaxy and waxy rice during storage were investigated by sensory evaluation and instrumental test by Instron. The result of sensory evaluation revealed more significant difference in most of texture characteristics than flavour. As the water to rice ratio increased, the moisture content of cooked rice increased and the value of moistness and plumpness increased but that of hardness decreased. Overall eating quality was the highest in cooked nonwaxy rice with 1.4(water/rice) and in cooked waxy rice with 1.2(water/rice). In the case of instrumental test, hardness showed highly significant difference and the value of hardness of nonwaxy cooked rice was greater than that of waxy cooked rice.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.248-248
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• 2017

This study was carried out to compare the cooking and antioxidant characteristics of cooked rice added at various rate of glutinous rice addition and treated with two cooking methods. Cooked rice added with glutinous rice was cooked by general and high pressure cooking method with and without fermented alcohol. Pasting characteristics of cooked rice were decreased as increasing the amounts of glutinous rice. Water binding capacity and swelling power were significant decreased with the amounts of glutinous rice increasing, however water solubility indices were significant increased. Palatability characteristics of cooked rice added with glutinous rice showed similar results to cooked rice without glutinous rice. Total polyphenol contents of cooked rice added with glutinous rice and fermented alcohol were significantly distinct, but there was no significant difference. Total flavonoid contents were increased as increasing the amounts of glutinous rice. Total flavonoid contents by general cooking method of cooked rice added with 20% glutinous rice and fermented alcohol were $23.20{\pm}0.61{\mu}g\;CE/g$. DPPH radical scavenging activities added with and without glutinous rice were 2.97~5.19 and 3.19~5.45 mg TE/100 g, respectively. ABTS radical scavenging activities by high pressure cooking method of cooked rice added with 20% glutinous rice and fermented alcohol were $19.48{\pm}0.63mg\;TE/100g$. In this study, cooking and antioxidant characteristics of cooked rice added with glutinous rice were expected to be used as basic data on manufacturing processed products.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.180-183
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• 2008

Digestion properties of 3 types of cereals, white rice, brown rice, and barley, were measured after cooking or grinding. Regardless of the processing methods, white rice showed the highest rate and the greatest extent of digestion, whereas barley showed the lowest values. During the early digestion period, cooked white rice kernels had a larger k (kinetic constant) value than uncooked white rice flour, indicating that cooking induced faster digestion than grinding. In the case of brown rice and barley, the cell wall in cooked kernels remained intact and resulted in a lower k values than those of uncooked flour. However, after 3 hr of digestion, the total digestion extent was greater for the cooked brown rice and barley than that for uncooked flours. The high content of slowly digestible starch (SDS) in cooked brown rice and barley might be due to the starch fraction which was protected by the cell wall. The resistant starch (RS) content, however, was greater for the uncooked flours than that for cooked kernels. The cooked kernels of 3 cereal samples tested showed higher glycemic index (GI) values than the uncooked flours.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.6
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• pp.1018-1024
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• 2009

The effects of the water extract of beef shank bones on the physical and sensory characteristics of cooked rice for JeonJu Bibimbap were investigated. Five kinds of cooked rice were prepared with 0%(control), 20%, 40%, 60%, and 100% of the beef shank bones extract. An increase in the beef shank bones extract concentration was associated with a lower moisture content of the cooked rice. The color(L, b value) of the cooked rice prepared with the beef shank bones extract became gradually darker during storage at $60^{\circ}C$. In regards to the textural properties of the cooked rice, the hardness increased with the addition of the beef shank bones extract and chewiness was changed in a similar pattern to that of hardness. However, the adhesiveness significantly decreased. In the sensory evaluation, the cooked rice prepared with 20 and 40% of the beef shank bones extract had the best sensory quality for JeonJu Bibimbap.

• Nutrition Research and Practice
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• v.1 no.1
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• pp.8-13
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• 2007

Cooked rice is a staple food for Koreans which provides more than 60% of daily required energy. In 1960's, Koreans ate 600 g-800 g of cooked rice per meal and the energy obtained from cooked rice was almost more than 80% of the daily intake of energy. However, as the economy of Korea improved, the major industry has been shifted from agriculture to various manufacturing industries and the export of those products has been increased thus increasing the national income but decreasing the farming population and thus rice consumption have been decreased. It has been said that the decreased rice consumption is caused solely by decreased farming population but it can also be said that the decreased farming population is caused by decreased rice consumption. As the national income increases, the type of foods people consume have become diversified. Various processed foods such as convenience food or ready-to-eat food have been widespread, which are mostly made of wheat flour rather than rice.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.142-149
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• 1999

Moisture absorption rate of rice according to the soaking time was higher at $25^{\circ}C$ than 4$^{\circ}C$ and the op-timum soaking time was 1hr at $25^{\circ}C$. When the ratios of added water for rice cooking were 1.3 in an elec-tric cooker and pressure cooker and 1.7 in an Dookbaeki sensory an mechanically evaluation of cooked rice were highly evaluated. The total number of peak on gas chromatography profile were 89 in an press-ure cooker 56 in an electric cooker and 83 in an Dookbaeki and major volatile compounds of cooked rice were aliphatic hydrocarbons cyclic hydrocarbons aromatic hydrocarbons aldehydes alcohols ketones and thiourea. Furan that is in sweety was not detected in volatile components of cooked rice of electric cooker.

• Korean journal of food and cookery science
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• v.12 no.1
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• pp.46-53
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• 1996

To investigate physicochemical and cooking properties of parboiled rice, choochung paddy processed to parboiled rice by three methods (PL, PT, PA) milled and examined hydration, cooking qualities and firming rate of cooked parboiled rice. The results were obtained as follows. The longer the steaming time during parboiling the larger EMC of soaked parboiled rice. Water uptake rate constants (k) of all the parboiled rice during soaking except for PT rice were generally increased than those of raw rice. The longer the steaming time during parboiling the greater volume increase rate constants ( $k_{v}$) of parboiled rice samples. The glelatinization temperature of parboiled rice flour by DSC was more increased than that of raw rice flour. Gelatinized entalpy was decreased and gelatinization content (%SG: degree of starch gelatinization) was increased by parboiling process. In cooking tests, parboiled rices were harder than raw rice and softness (reciprocal of hardness) was greater PT30, PA, PL30 in turns the cooking time of the parboiled rice took longer 3-10 min than that of raw rice, PL30 took longer time than anyother rices. Cooking water of parboiled rices could be observed lighter turbidities than that of raw rice. Firming rate constants of cooked rice during storage 24 hours were generally decreased by parboiling-processing. The time constants, reciprocal of firming constants of cooked PL30 rice were 2 times slower than those of cooked raw rice.e.

• Korean journal of food and cookery science
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• v.23 no.4 s.100
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• pp.452-460
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• 2007

As a preliminary study for developing cooking techniques to improve cooked rice flavor, we surveyed consumer perceptions on purchasing rice and the consumption of cooked rice. The quantity of rice purchased by consumers was in the range of $1O{\sim}20$ kg. The purchase criterion for 50% of the subjects was the taste of the cooked rice, and half of the subjects bought their rice at a supermarket. A majority (90%) of the subjects consumed the rice within 1 to 4 months, storing it raw in the package (32.4%) or in a container at room temperature. The rice was cooked for 2 to 5 persons (65%), 1 to 2 times a day (70%) with a pressure cooker (76%). The rice and water volume were measured by eye. The cooked rice was eaten immediately (41.8%) or in 1 to 2 days (48.6%) by keeping it in an electric cooker (63.6%). The subjects perceived the rice cultivar (37.9%) as the major factor for the cooked rice flavor, as well as the region of origin (21.3%), and storage period (11.9%); the cultivars of Ilmi, Ilpoom and Chuchung were preferred. In conclusion, the consumers regard rice as a principal food; however, the methods to measure rice and water are not standardized. To improve the taste of cooked rice, consumers depend on cooking equipment and the rice cultivar.