• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.136-139
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• 2002

The discrimination of the agricultural origin, especially locally produced of imported products such as black rices was investigated by using electronic nose. Volatile components from these products were discriminated by six metal oxide sensors without pretreatment. Pattern recognition was carried out. Principal component analysis showed the differences between imported and locally produced ones. The number of 57 from 69 species of black rices were recognized as locally produced one (83.33%) and 11 from 13 species one (imported black rices) was correctly discriminated. Unknown habitat of black rice could be identified by artificial neural network system whether the imported or not. Also commercial electronic nose (E-nose 5000) that was combined with metal oxide sensor and conducting polymer sensor showed 92.75% (locally produced black rices) and 92.31% (imported one) of discrimination.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.434-440
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• 1996

This experiment were conducted to elucidate the damage by viviparity during grain filling on grain quality and hulling recovery and to understand the varietal differences of viviparity and the effect of extractive from rice hull of hardly viviparous varieties on seed germination and seedling growth. Ten rice cultivars, such as three indica, four japonica and three Tongil-type rices, were used in this study. The brown rice yield was decreased along with increasing the artificial viviparous treatment periods. At six days after treatment, brown rice yield of Daeseongbyeo was reduce 20% as compared with control. The ratio of head rice was 41.3% at six days after viviparous treatment with $25^{\circ}C$ temperature and over 95% relative humidity, while it was 99.5% in control. Varietal differences of viviparity in three rice groups were ranged from 1.1 to 5.2% in indica rices, 9.2 to 79.7% in japonica rices and 2.1 to 63.7% in Tongil-type rices. Methanol extractives from rice hull of IR36, Shinunbongbyeo and Jungwonbyeo inhibited significantly the germination of Deaseongbyeo.

• Korean journal of food and cookery science
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• v.27 no.6
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• pp.735-743
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• 2011

This study examined physicochemical properties of rice grains and qualities of cooked white rice of the high yielding, Japonica type, specifically Druryechanbyeo and Boramchanbyeo, and of the Tongil-type, specifically Hanarumbyeo and Andabyeo. The changes of water absorption rate of rice grains, their textural properties and a sensory evaluation of the cooked rice s were analyzed. All varieties were short grain. The length and width of Tongil type rice grains larger than those of Japonica type. The water absorption of white rice grains increased rapidly until 1 hr when soaking and after that increased slightly. The water absorption of Druryechan grain was higher than that of the Boramchan. The sensory evaluation results showed that the Japonica type cooked rices had a higher value for overall quality than the Tongil type cooked rices. With regard to the textural properties of the cooked rices, the hardness of Boramchan and Hanarum varieties showed higher than that of Druyechan and Anda varieties. Adhesiveness, springiness and chewiness were not significantly different between varieties (p<0.05).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.207-213
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• 1999

Thirty-eight glutinous rice varieties were classified into nine groups on the scatter diagram by the upper two principal components (56% contribution to the total information) based on eleven physicochemical characteristics including the viscograms and physical properties of cooked rice. The first principal component was the factor mainly associated with the viscogram characteristics of rice flour emulsion and the second was the factor chiefly related to the physical properties of cooked rice and water absorbability of rice grain. Indica glutinous rices were clearly distinguished from japonica ones by the first principal component score. Javanica glutinous rices were widely distributed on the intermediate zone between indica and japonica or on several japonica rice groups. Significant positive or negative correlations were found among water absorption rates of rice grain, physical properties of cooked rice, and viscogram characteristics of rice flour. Especially in japonica glutinous rices, the breakdown and setback viscosities of rice flour were closely associated with the alkali digestion value of milled rice and the stickiness of cooked rice. The frequency ratio of short glucose chains (A-chain) to intermediate glucose chains (B-chain), the ratio of B- chains to long glucose chains (C-chain) and the relative frequency of A- or B-chain fractions representing the amylopection structure of rice starch was closely associated with the breakdown and setback viscosities of rice flour.

• 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.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.21-25
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• 1991

Twenty-six japonica and 19 Tongil type milled rices were grouped based on water uptake rate at $23^{\circ}C$ and interrelationships between starch properties and hydration group were investigated. There were no significant differences in relative crystallinity, transmittance increase rate of 0.1% starch suspension and soluble amylose between japonica and Tongil type rices. The gel volume of starch n 3M KSCN solution of Tonsil type rice starch was significantly higher than that of japonica one. However, no correlations were observed between starch properties and hydration groups.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.55-70
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• 2001

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21~23$^{\circ}C$ for 40 days after flowering, increased with long anomalies in 1998~99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than norm in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Togil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than japonica rices, photoperiod-sensitive and thermo-sensitive ecotypes.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.933-940
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• 2015

The objective of this study was to determine quality changes in seed germination rates and lipid components in Japonica and Tongil (indica/japonica) type brown rices with different tocol composition during storage. Moisture content, seed germination rate, crude lipid content, fat acidity, tocol content, free fatty acid composition of brown rice and pH of milled rice were measured to evaluate their quality after storage. Seed germination rates of stored Japonica and Tongil type brown rices were decreased by 22.4% and 59.7%, respectively, after 8 weeks of storage. The fat acidity of Japonica rice was significantly (p<0.05) higher than that of Tongil type brown rices after storage. The major tocol homologue of Tongil type was ${\gamma}-tocotrienol$, whereas, major tocol homologues of Japonica brown rices were ${\alpha}-tocopherol$ and ${\alpha}-tocotrienol$ throughout the entire storage period.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.455-460
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• 2001

Quality characteristics of rice which was washed with solution of waxy rice flour to improve the quality of long term stored rice, were investigated. 2000 (Hap-Sal) and 1996 crop year rices (Jung Bu Mi) which were pre-washed with water (PWR) and solution of waxy rice flour (PWRW) were compared. Moisture contents of rices showed no difference among rices, and protein contents of PWRW were increased with washing of waxy rice flour solution although PWRW and PWR were processed from the same batch. Micro-structure of rices did not show particular difference enough to explain quality characteristics of rices. Amylogarm of PWR showed higher viscosity than Hap-Sal, which was characteristic properties of long term stored rice. However, viscosity of PWRW was decreased compared to PWR. The reason of decrease must be the effect of waxy rice starch which was imbedded with washing the rice. Color of PWR was higher in lightness (L), whiteness (W) and yellow (b) compared to Hap-Sal and PWRW. However cooked PWR showed decrease of whiteness and increase of yellow. Sensory evaluation of PWRW showed significant improvement of glossiness, stickiness, taste, and overall preference and decrease of yellow and hardness compared to PWR. Above results suggest that the development of PWRW will improve the quality of pre- washed rice.

• 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.