• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.288-295
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• 1999

Nineteen japonica and Tongil-type rices were selected from seventy nine Korean and Japanese rice cultivars grown in 1989 based on the water uptake behavior of milled rice under the room temperature and boiling conditions. The selected rice cultivars were investigated for water absorbability and some physicochemical characteristics of milled rice, proper water amount for cooking and sensory evaluation of cooked rice. The relationships among the tested grain properties were also examined. The highest varietal variation of water uptake rate was observed at twenty minutes after soaking in water. The maximum water uptake of milled rices at room temperature occurred mostly at about eighty minutes after soaking in water. Newly harvested rices showed a significantly lower water uptake rate of milled rice at 20 minutes after soaking, a relatively higher maximum water absorption ratio under the room temperature, and the less water uptake and volume expansion of boiled rice compared with the one-year old rice samples. 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 ansd 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 averaged to 2.63(in v/v basis). The water amount needed for optimum cooking was the lowest in Cheongcheongbyeo (Tongil-type rice) and the highest in Jinbubyeo, and the amount could be estimated with about 70% fittness by the multiple regression formula based on some water uptake characteristics, ADV and amylose content of milled rice as the independent variables. Nineteen rice cultivars were classified into seven groups based on scatter diagram projected by principal component analysis using eight properties related to water uptake and gelatinization of milled rice.

• Journal of the Korean Society of Food Culture
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• v.10 no.2
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• pp.101-106
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• 1995

The effects of ${\alpha}-rice$ flour on the physicochemical properties of Korean rice cake were investigated. Before cooking, the degree of gelatinization of rice cake without ${\alpha}-rice$ flour was 5.75%, but 16% for adding ${\alpha}-rice$ flour. After cooking, the degree of gelatinization of rice cake were increased from 52% to 85% by adding ${\alpha}-rice$ flour. The L value of rice cake with ${\alpha}-rice$ flour increased, but there was no significant difference in L value between samples. The hardness of rice cake before and after cooking were increased by adding ${\alpha}-rice$ flour whereas after frozen stoarge there was no apparent effect on the color values of rice cake. The water absorption ratio of rice cakes during cooking were increased by addition of ${\alpha}-rice$ flour. Scanning electron photomicrographs revealed that the rice cake with ${\alpha}-rice$ flour has more porous structure with rapid rehydration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.5
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• pp.737-744
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• 2010

In order to provide fundamental data on development of rice noodles, the quality characteristics of 10 kinds of commercial rice noodles were evaluated. Rice noodles were categorized into 3 groups for examination: 100% rice noodles with different shapes; round shape noodles with different rice contents; and noodles with different rice contents but smilar cooking method. Cooking properties, texture measurement, and sensory characteristics were evaluated. Frozen rice noodles and instant type of noodles made from composite flour of rice and wheat flour exhibited higher scores in overall acceptance. As for the form of noodle, round-shaped noodles seemed to be preferred in comparison to flat-shaped noodles. Generally, noodles with high texture scores of cohesiveness, adhesiveness, chewiness, resilience but not high score of hardness having smooth surface were preferred affecting overall acceptance scores. It appears that cooking methods and cooking time recommended by manufactures, noodle thickness and shape, packaging types such as frozen, refrigerated, and dried noodles were more influential than rice contents in aspects to the quality characteristics of the commercial rice noodle products in this study.

• Journal of the Korean Society of Food Culture
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• v.20 no.3
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• pp.293-298
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• 2005

This study was investigated to examine the physicochemical properties of functional rice and the adaptable food processing of the added functional rice. The functional rice are Sanghwang rice, Agaricus rice(fermented with basidiomycota), Tochukaso rice, fermented with Monascus rubber rice. Fermented with Monascus rubber rice contains more crude protein, curde lipid, moisture, and total dietary fiber. The cross sectional shapes of the functional rice show polygon shapes, the starch granules of those rice are transformed. In sensory evaluation, fermented with Monascus rubber rice was showed the lowest values for glossness, color, flavor, sweetness, harshness, overall acceptability. The textural properties for those ratios were also affected by the period of storage. After 48 hours, the lowest hardness level was 30% Tochukaso rice addition, and the highest hardness level was 10% Sangwhang rice addition case. In 30% Sangwhang rice, and 30% tochukaso rice case gumminess values were decreased after 48 hours. But in 30% Sangwhang rice, and 30% Tochukaso rice case, the chewiness values decreased. This result suggest that the most suitable addition ratio for the rice cooking condition is 10% functional rice addition.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.97-107
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• 1981

This study was carried out in order to provide the basic data necessary to develop the effective and desirable cooking method on large scale for investigating the physical characteristics of cooked rices and studying optimum cooking conditions by pressure in kettle cooking rices. Milyang-15, local Japonica type and Milyang-23, high yielding Indica type major varieties cultivated in Korea were used as cooking sample after polishing 70% and 90% respectively, and the results obtained are summarized as follows. 1. The average moisture content of cooked rice by open kettle and pressure kettle method in typical households were 65.17% and 64.52%, respectively. 2. In water absorption capacity of rice grain Milyang-23 was 4.5% higher than Milyang-15, and maximum water content after absorption in Milyang-23 was 29.14%. 3. The expansion volume of cooked rice was changed proportionally by water absorption, heating temperature and time, and maximum expansion volume of cooked rice was 3.2 times greater than rice grain. 4. The gelatinization degree of cooked rice intensively concerning in hardness of rice grain was increased as water-to-rice ratio, heating temperature and time increased, and it was 0.44 in Milyang-23 and 0.64 in Milyang-15 under the optimum cooking conditions as 160% water-to-rice ratio, $0.2kg/cm^2$ cooking pressure and 25 minutes cooking time. 5. The hardness of cooked rice was decreased as water-to-rice ratio, heating temperature and time increased, and it showed 2.35kg/wt in 90% polished Milyang-23 and 2.0kg/wt in 90 polished Milyang-15 under optimum cooking conditions. For maintaining the same level of hardness of cooking rice Milyang-23 required 25% much more water than Milyang-15. 6. The elasticity of cooked rice was changed proportionally by water-to-rice ratio, heating temperature and time, and it appeared 19.2mm and 15.7mm in 90% polished Milyang-15 and Milyang-23 respectively. 7. The gumminess of cooked rice was decreased as water-to-rice ratio, heating temperature and time increased, and it showed 60 and 73 in 90% polished Milyang-23 and Milyang-15, respectively. 8. The optimum cooking time on differerent pressure in kettle took 25 minutes at $0.2kg/cm^2$, 20 minutes at $0.4kg/cm^2$, 15 minutes at $0.6kg/cm^2$, and 10 minutes at $0.8kg/cm^2$.

• Journal of the Korean Society of Food Culture
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• v.5 no.4
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• pp.415-423
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• 1990

'The Joobang' is a cooking book written purely in Korean which came from a Mr. Lee. It is unknown when and by whom this book was written, but it is inferred from red pepper mentioned in this book and from Korean-writting type that the book was written around in the mid-nineteenth century. The contents of 'the Joobang' consist of thirty seven items in all : sixteen items of rice alcoholics, five side dishes, eleven Tucks(rice cakes) and Guaja(cookies) and five processed materials. Cereals for making rice alcoholics were regular rice and sticky rice. In the first brew, rice alcoholics is made all from regular rice, and in the second brew, fifty six percent of regular rice and forty four percent of sticky rice was made use of. For five items of alcoholics forming 31.3% of alcoholics, flour was added, in which case the proportion of leaven to cereals was lower. There were four types of processing cereals in brewing rice alcoholics Jee-ae-bop(steamed rice, 60.9%), thick gruel with cereals ground and completely cooked(8.7%), thick gruel with cereals ground and half cooked (26.1%) and GooMung Tuck(doughnut-shaped rice cake, 4.3%). The comparison of the materials for brewing rice alcoholics and of the types of processing cereals presented in the seven cooking books purely in Korean(Umsik Deemeebang, JoobangMoon, Umsikbo, Sool-mandununbop, Kyuhap chongseo. The Kims' Joobangmoon and The Lee's Umsikbup) showed us the following facts ; Yihwajoo (rice alcoholics brewed around the blooming time of pear trees) and Kwahajoo(rice alcoholics which passed the summed time) were most often introduced and commonest, and the materials for brewing and the types of processing little changed over times. The materials for side dishes were all animal food, and vegetable food was little used for side dishes. Red pepper was used for seasoning. It is a problem of Korean traditional cooking that there were no units of measuring for side dishes. The main materials for Tuck(rice cakes) and Guaja(cookies) were sticky rice, regular rice and honey. There was a variety of terms for the process, from which we can see that the procedures of making Tuck(rice cakes) and Guaja(cookies) were very complicate. Processed materials were chiefly made of sticky rice and the material of firewood(oak trees) and the strength of fire(fire burning vigorously and fire turning to ashes) were described.

• Journal of the Korean Society of Food Culture
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• v.17 no.1
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• pp.78-89
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• 2002

Preferences of 814 elderly living in Incheon for dishes, food materials and cooking methods were investigated. The survey was conducted from Dec. 2000 to Jan. 2001 by questionnaires. Subjects preferred cooked rice with beans, kalkooksoo(hot noodle), gomtang(soup with beef), bibimbap(rice with assorted mixture) to other staple dishes. However, preference for hashed rice or curried rice was very low. More than 50% of the subjects liked soybean paste soup and stew, and the ratio of elderly who liked Chinese cabbage kimchi was 68.7%. There was no significant difference in preference for pan-fried foods according to food materials in them. Subjects liked injolmi(waxy rice cake), shikhye(fermented rice drink) and coffee the most. Most subjects preferred plant foods like vegetables, legumes and seaweeds to animal foods. Preference of elderly for milk and yoghurt was reatively high; however, that for ham, butter and cheese was low. Elderly in Incheon liked roasted beef, beef soup and roasted pork the most. Chicken was preferred when it was boiled in water with garlic, ginseng, and so on. Cooked and seasoned vegetables (Namul) were the most preferred type by elderly. Preferences for dishes and food materials were more affected by living places of the subjects than by sex, and the reverse was true in preference for cooking method of food materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.2
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• pp.69-74
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• 1987

The effects of soaking temperature on hydration and cooking rates of Chunmabyeo(Japonica) and Kayabyeo(J/Indica) rice were investigated. Water uptake and volume increase rates of milled rice were increased as a function of soaking temperature$(4^{\circ}C{\sim}30^{\circ}C)$. The rate of volume increase of milled rice was greater than that of weight increase, which was more pronounced at low soaking temperature. The soaking of milled rice prior to cooking had a definite effect on the degree of gelatinization. The soaked milled rice was more easily gelatinized than unseated one. The water uptake rate, volume increase rate, degree of gelatinization and cooking rate of milled rice were faster in Kayabyeo than Chunmabyeo.

• Food Science and Preservation
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• v.11 no.3
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• pp.325-330
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• 2004

This study was conducted to investigate optimal processing conditions, cooking characteristics, antioxidant activity and packaging method of rice coated with bamboo extract. In sensory evaluation of cooked rice, rice coated with bamboo ethanol extract was higher smell and taste than the other extraction methods, but texture showed no difference. As coating concentration increasing, L, a and b values of coated rice were increased. But L value of coated rice after cooking was decreased. On sensory evaluation of cooked rice, smell and taste were best in 10$\%$ coated with bamboo ethanol extract. Mineral contents of coated rice with bamboo extract were higher than those of uncoated. Water absorption and volume expansion of coated rice were lower than uncoated rice but showed higher toyo value. Hardness, gumminess and chewiness values of cooked rice with coated rice were higher than uncoated rice. Antioxidant activity of coated rice was higher than uncoated rice about twice times. Toyo values and alkali digestive values of coated rice were highest in paper package than the other packaging conditions. The total bacterial counts of rice coated with bamboo extract after cooking was lower than uncoated rice during storage at 25 and 6O$^{\circ}C$.

• Proceedings of the Korean Environmental Health Society Conference
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• 2002.04a
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• pp.55-56
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• 2002

Aflatoxin is a secondary fungal metabolite and is a public health hazard because it is a human carcinogenic and has many deleterious effects in men and animals. Rice is one of the better substrates for the fungus which can produce aflatoxins. This study was performed to investigate aflatoxin reduction during the cooking and processing of rice. Aflatoxin was produced by Aspergillus parasiticus ATCC 15517 on well-milled rice(Japonica type) at the level of 13.2 ppb. Cooked rice, rice cakes (baek-sol-gi, plain steamed rice bread), fermented rice (sik-hye, sweet rice beverage), and popped rice were prepared from the aflatoxin-contaminated rice. Aflatoxin content in the samples was determined by high performance liquid chromatography. The total aflatoxin level was decreased to 46.9％ in the cooked rice, 85.6％ in the rice cakes, 11.4％ in the fermented rice, and 7.6％ in the popped rice, respectively (p＜0.05). This reduction brought the level of aflatoxins down to below the Standard and Specification of Korea (10 ppb), except for the rice cakes. These results indicate that washing, steaming, fermentation, and popping of rice was helpful in reducing the aflatoxin level in the rice and the most helpful factors were high temperature & high pressure. More research is needed to understand why the preparation of rice cakes did not reduce the level of aflatoxin as much as the other cooking methods.