• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.355-363
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• 1999

The experiments were carried out to elucidate the varietal variation of retrogradation in aged cooked rice and its association with some physicochemical properties of milled rice. The fifteen rice materials were selected from forty-three low-amylose japonica and Tongil-type rice cultivars based on palatability and retrogradation of cooked rice stratified by preliminary sensory evaluation of warm and cooled cooked rice. One japonica glutinous rice variety was included for comparison of retrogradation of cooked rice. The $\alpha$-amylase-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The desirable checking time for evaluating the varietal difference in deterioration of aged cooked rice was four hours after storing in room temperature and two hours after preserving in refrigerator based on the largest coefficients of variations in degree of retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. The retrogadation index represented by the percentage of retrogradation difference between warm and cooled cooked rice to original estimates of warm cooked rice was significantly affected by the degree of retrogradation of cooled cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked nce. The varietal difference in retrogradation of cooked rice can be effectively classified by scatter diagram on the plane of upper two principal components based on some retrogradation properties of cooked rice. The deteriorated structural change in cooled cooked rice by observing through the scanning electron microscope was more conspicuous in the fastly retrograded cooked rice than in the slower one.

• The Korean Journal of Food And Nutrition
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• v.6 no.3
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• pp.189-198
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• 1993

This study was carried out to investigate the effect of medium-cooked rice on brewing of yakju which was a traditional rice wine in Korea. The influences of cooking temperature of rice on hydrolysis of rice starch and rice protein were tested, and experimental brewings were done according to the traditional brewing method of Bangmunju in which some medium-cooked rice was used. The results obtained were as follows The hydrolysis of starch and protein in medium-cooked rice at 60~$65^{\circ}C$ was easier than that of full-cooked rice at 80~10$0^{\circ}C$. The amounts of saccharides, total amino acids and extracts In Yakju brewed with the combined use of medium-cooked rice and full-cooked rice were twice as much as those brewed with full-cooked rice only. The results of sensory test of Yakju brewed with the combined use of medium-cooked rice and full-cooked rice were better in taste, color and flavor than those brewed with full-cooked rice only. It was thought that our ancestor's traditional brewing method of Yakju in which medium cooked rice and full-cooked rice were used combinedly was excellent Judging from zymological point of views.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.777-784
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• 2007

The purpose of this study was to provide the descriptive sensory profiles for cooked rice by various rice cookers, losing descriptive analysis. The rice samples cooked in an electric pressure cooker, and in pressure cooker B, were separated by roasted flavor, sweetness, burnt flavor, cooked rice flavor, moistness, cohesiveness, and chewiness using PCA. The rice cooked in pressure cooker A was harder and rougher, and showed grain wholesomeness, but it still had a cooked and burnt flavor. The rice cooked in a stone cooker and an electric rice cooker was less hard, and showed less grain wholesomeness, but it had a burnt, cooked rice, and less raw rice type of flavor. Finally, the RTE (ready-to-eat) rice showed more grain wholesomeness, and had more raw rice and sour flavor.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.464-472
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• 2017

The qualities of rice cooked on heat plate, induction heat and heat plate with pressure, were investigated. The weight, volume, water soluble index (WSI), hydration by SEM (Scanning Electron Microscope), and gelatinization by DSC (Differential Scanning Calorimetry), as well as the consumer acceptability of cooked rice were analyzed. The weight, volume and WSI of rice cooked on heat plate with pressure were higher than those of rice cooked on heat plate and induction heat. The rice cooked on heat plate with pressure also showed higher degree of hydration and gelatinization, and lower degree of enthalpy of gelatinization than the rice cooked on heat plate and induction heat for 5~15 min. The consumer acceptability revealed that the odor, appearance, taste, texture and overall acceptance of rice cooked on induction heat were better than those of rice cooked on heat plate and heat plate with pressure. During storage in a cooker for 0~12 h, there was a decrease in the consumer acceptability of cooked rice. Overall results indicate that the qualities of rice cooked on induction heat and heat plate with pressure were higher than those of rice cooked on heat plate.

• Korean Journal of Community Nutrition
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• v.6 no.4
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• pp.686-702
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• 2001

The purpose of this study is to suggest the menu patters of people in Kangbukgu for the basic data of the nutrition education program in its health center. The dietary intake was investigated by the 24-hour recall method for 488 subjects. To analyze patterns, dishes were classified into major staple food, kimchi, soup and side dishes and also classified into 24 categories by cooking method. Patterns by the kind of dishes for the subjects were cooked rice + soup + kimchi 〉noodle + kimchi > cooked rice + kimchi in the order of frequency of use. Patterns for breakfast were, cooked rice + soup + kimchi > coated rice + soup + two dishes of kimchi. For lunch, patterns were, noodle + kimchi > footed rice + kimchi = cooked rice + soup + kimchi. For dinner, patterns were, cooked rice + soup + kimchi = cooked rice + kimchi > noodle + kimchi. Results of analyzing by the number of dishes, were cooked rice + soup + kimchi + one side dish 〉cooked rice + soup + kimchi + two side dishes. It was significantly different by meal(p<0.01). The results of analyzing patterns for the main staple foods were cooked rice〉noodle > bread in that order. It was significantly different by meal(p<0.01). The results of analyzing patterns, with those considered basic food, cooked rice, soup and stew, were cooked rice + soup > cooked rice > cooked rice + stew. It was significantly different by meal(p < 0.01). With these results, the menu patterns of people in Kangbukgu were different by meal. The main dish was mostly cooked rice and the menu has the traditional menu patters, composed of cooked rice, soup and kimchi.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.39-74
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• 2001

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s∼1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great, progress and success was obtained in development of high-quality japonica cultivars and qualify evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice caltivars and special rices adaptable for food processing such as large kernel, chalky endosperm aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic mcroscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high Probability of determination. The ${\alpha}$ -amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice bread. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

• The Korean Journal of Food And Nutrition
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• v.8 no.4
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• pp.330-334
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• 1995

A various aseptic packaged cooked rice prepared In Korean rice was developed for extending shelf-life at room temperature. Data of proximate composition showed no significant difference between cultivars except moisture of cooked rice. The optimal condition of added water content for aseptic packaged cooked rice was 1.3 times of rice while 1.5 times for cooked rice and microwave heating. Hardeness of cooked rice was decreased in order of Dongjin, Odae, Chuchung, Kyaehwa, Ilpoom. Sensory evaluation results showed that Ilpoom had a best result while Odae for storage time (7 days).

• Journal of the Korean Home Economics Association
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• v.35 no.2
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• pp.147-157
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• 1997

It attempted to determine the effect of various thawing methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature, on the quality of frozen cooked rice using Nongan variety of rice. These effects were analysed at three different periods-after 10 days, 30 days and 90 days. It conducted a physico-chemical analysis(moisture content, dehydration rates, color value and texture) and sensory evaluation o the frozen-thawed cooked rice. The study showed that there were no significant differences 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 of 90 days. However, the thawing method of pressure cooking caused high moisture content and decrease in hardness on the cooked rice, the desirability for the rice didn't diminish compared with the cooked rice just after cooking. the quality characteristics of the cooked rice after frozen-thawing by conventional cooking and microwave heating were similar with that of the cooked rice just after cooking. thawing at room temperature caused a significant decrease in quality characteristics.

• Korean Journal of Community Nutrition
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• v.6 no.5
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• pp.809-818
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• 2001

The purpose of this study was to fad the specific character of menu patterns by sex, age and health risk of subjects for the basic data of a nutrition education program. The dietary intake of the subjects was investigated by the 24-hour recall method. Subjects consisted of male 94, female 394, total 488. To analyze patterns, dishes were classified into major staple foods ; kimchi, soup and side dishes and also classified into 24 categories by the cooking method. For the men, a frequently served pattern was cooked rice + soup + kimchi. For the women, the pattern was also cooked rice + soup + kimchi. For the 20-49 year olds and the 50-64 year olds, frequently served patterns were cooked rice + soup + kimchi > noodle + kimchi. For the 65-74 year olds, those patterns were cooked rice + stew > cooked rice + kimchi. For the normal group and the risk group, the frequently served pattern was cooked rice + soup + kimchi. The most used menu pattern by the number of dishes was cooked rice + soup + kimchi in the male, female, normal group and risk group. For the 20-49 year olds, the pattern was cooked rice + soup + kimchi and noodle + kimchi. For the 50-64 year olds, it was cooked rice + soup + kimchi. For the 65-74 years old, it was cooked rice + stew. The result of analyzing patterns for the most used main staple food was cooked rice in all groups. The results of analyzing patterns, with those considered basic food, cooked rice, soup and stew, showed that frequently served patterns were cooked rice + soup > cooked rice > cooked rice + stew in all groups. With these results, we can summarize that the menu patterns of people in Kangbukgu was the younger, the more non-traditional. Also, the normal group had more various patterns than those of the risk group. Thus, we need further research about menu patterns to provide adequate nutrition education.

• Journal of the Korean Society of Food Culture
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• v.19 no.3
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• pp.359-368
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• 2004

The Physicochemical, sensory and cooking properties of functionally fortified rice with dietary fiber and chitosan were compared with regular rice when the rices were cooked with pressure and electric cookers. Moisture content of functional rice before cooking was 11.11%, which was lower than 13.72% in regular rice. Accordingly, moisture contents of functional rice samples cooked both with pressure and electric cookers were lower than those of regular rice. L value showing the degree of lightness of cooked rice was significantly higher in rice samples cooked with pressure cookers. The ${\alpha}$ value, the degree of redness and the b value, the degree of yellowness, were the highest in the functional rice cooked with an electric rice cookers. Textural measurement of hardness using a rheometer showed the highest value in functional rice cooked with a pressure cooker. The degree of gelatinization measured using differential scanning calorimetry (DSC) before cooking showed higher onset gelatinization temperature ($T_0$) and peak gelatinization temperature ($T_p$) in functional rice compared with those in regular rice. The gelatinization enthalpy (${\Delta}H$) of functional rice was lower than that of regular rice, showing that functional foe had lower gelatinization energy compared with regular rice. When the samples were stored in a refrigerator for one week, the DSC showed faster retrogradation degrees in samples cooked with electric rice cooker, having significantly higher enthalpies of regular and functional rice cooked with electric cooked compared to those cooked with pressure cookers. The functional rice samples cooked with pressure cooker had higher consumer acceptance test values compared to those cooked with electric cookers.