• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.157-165
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• 2017

Being a staple food for more than half of the population of the world and South Korea, rice is an important crop. For the past 20 years, global paddy rice cultivation area and production have shown an annual growth of 0.46% and 1.61%, respectively. Global rice consumption for food and processing has increased by 1.37% and 3.68%, respectively. Due to the main reason for such increasing human population, it is expected that from 439 million tons in 2010, additional 116 million tons will be needed in 2035. Global rice imports and exports have doubled in the last 20 years. However, in spite of such increment, global rice exports in 2013 were 8.4% of the total production. It is thought that rice protection policies in the producing countries are the main reason for such small scale of rice trading. In the past 5 years, India recorded the largest growth rate in rice exports (51.4%), whereas China showed the largest growth rate in imports (61.0%). For global utilization of milled rice during the same period, approximately 79.4% was used as food, 7.2% as animal feeds, and 1.4% for processing. Regionally, Asia has shown a similar pattern to the global rice usage, whereas utilization for processing in America, for food in Africa, and for animal feed in Europe was relatively higher than the global rice usage. Korea's cultivation area and production since the last 5 years, are 0.5% and 0.8% of those of the world, respectively. Its annual rice export is approximately 3,000 tons, which is 0.01% of the global rice export. Korea's rice utilization is high for food and low for feed and for processing relative to global rice utilization. Therefore, a review must be conducted to increase Korea's utilization of rice for processing and for feed production.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.296-305
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• 2002

Rice yield and grain guality were investigated with treatments of silicate fertilizer, straw compost and NPK fertilizer in the paddy soil of silty clay loam from 1975 to 2001. Rice yield of the treatments of silicate fertilizer. $1,500kg\;ha^{-1}$ and straw compost $10,00kg\;ha^{-1}$ were increased by 15%, 10%, respectively, for 27years average yield in comparison with NPK plot. In the plots of NPK+silicate fertilizer $1,500kg\;ha^{-1}$, NPK+silicate fertilizer $2,500kg\;ha^{-1}$, taste value(Toyo instrument) of cooked rice and quality assessment were higher than those in NPK control plot and NPK+straw compost $10,000kg\;ha^{-1}$ plot, but the contents of crude protein, amylose of milled rice grain were lower than those in other treated plots. Nitrogen and phosphorous contents of rice plant were lower, but $SiO_2$ content were higher in the treatment of silicate ferti lizer 1,500, $2,500kg\;ha^{-1}$ than straw compost $10,000kg\;ha^{-1}$ plot. Rice quality assessment was positively correlated with taste value, but it was negatively correlated with crude protein and amylose content of milled rice grain. Ratios of Mg/N, $Mg/N{\cdot}K_2O$, $SiO_2/N$, $SiO_2/P_2O_5$ and $SiO_2/K_2O$ were positively correlated with taste value and quality assessment of rice grain, but negatively correlated with crude protein, amylose and fatty acid content. In soil chemical characteristics related with rice quality after experiment in 2001, soil pH and $SiO_2$ content were positively correlated with taste value and quality assessment of rice grain, but contents of soil $P_2O_5$, ex-K were negatively correlated with them.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.193-202
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• 2017

This study was carried out in 2014 and 2015 to investigate the effect of transplanting density on panicle production and to analyze the relationship of panicle production with yield traits in the mid-maturing quality rice cultivar 'Haiami' in the mid-plain area of Korea. Number of tillers per square meter increased by reducing planting distance and increasing seedling number per hill. These effects were maintained until maturity and were reflected in the final number of panicles per square meter, although the effect of planting density decreased as rice growth progressed. However, increased panicle number per square meter following dense planting did not improve head rice yield. Panicle number per square meter was negatively associated with spikelet number per panicle and was not correlated with other yield components or head rice yield. Head rice yield was not correlated with head rice percentage but was closely and positively correlated with milled rice yield. Milled rice yield did not increase with grain filling percentage but increased with spikelet number per square meter. Spikelet number per square meter increased with both spikelet number per panicle and panicle number per square meter, although the former had a greater influence. Therefore, we conclude that head rice yield of the 'Haiami' cultivar grown in the mid-plain area of Korea is not improved with an increased panicle number following high planting density but it could be improved with high milled rice yield by increasing spikelet number per unit area.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.294-299
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• 1989

The quality of dehydrated instant rice produced by a few selected processing methods with short grain milled rice was evaluated. Instant rice produced by process 2 had high rehydration rate, and those by processes 1 and 2 revealed light brown color with less lightness. Instant rice produced by processes 1 and 2 with ammonium carbonate treatment had more uniform porous microstructure, as shown by SEM micrographes, and microstructural difference was noticed between instant rice prepared with government rice and Akibari. Instant rice produced by processes 1 and 2 had less sensory color score, and those by processes 2 and 4 had higher sensory cohesiveness. Overall quality of instant rice produced by process 2 was better, except color.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.28-36
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• 1992

Fifty rice varieties were tested for alkali digestibility of milled rice grain at four different KOH levels, and twenty-four varieties selected were tested again for alkali digestibility at different degrading times and KOH levels. Gelatinization rate at several heating times and heating temperatures, and water absorption rate at 21$^{\circ}C$ and 77$^{\circ}C$ water temperatures were observed using rice samples of twenty-four varieties to clarify the relationship between alkali digestibility response, gelatinization rate and water absorption rate. Varietal difference of ADV in Japonica and Tongil tye rices was biggest at KOH 1.2%, but it was better to test at KOH 1.2% and 1.4% levels to know the exact alkali digestibility response of rice varieties. Rice varieties tested could be classified into three groups, low, intermediate and high, based on their alkali digestibility response at four KOH levels, and most of Korean cultivated rice varieties were belonged to intermediate or high ADV group. Varietal variation was also found in alkali degrading response at different soaking times in alkali solution. Low ADV varietal group showed higher gelatinization temperature and needed longer heating time for complete gelatinization compared with intermediate or high ADV group. Same trends was found between intermediate and high ADV groups, but varietal variation in the same ADV group was also found in gelatinization temperature and heating time needed for complete gelatinization of rice grain. Water absorption rate of low ADV group was lower than intermediate or high ADV group both at 21$^{\circ}C$ and 77$^{\circ}C$ water temperatures, and intermediate ADV group showed lower absorption rate than high ADV group only in initial water absorption stage at 21$^{\circ}C$.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.46-49
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• 2003

Paddy and milled rice quality, milling characteristics, energy consumption of milling process were investigated using Dasanbyeo, Ansanbyeo, Hwaseongbyeo, Ilpumbyeo, and Donganbyeo varieties. Thousand grains weights of the varieties dried to 15% moisture content were 22.92-28.60 g, with Dasanbyeo being the heaviest. Optimum clearance of rubber roller for obtaining maximum dehulling recovery was 30% of each rice variety thickness. At that time, perfect brown rice ratios of Dasanbyeo, Ansanbyeo, Hwaseongbyeo, Ilpumbyeo, and Donganbyeo were 95.24%, 98.86%, 95.97%, 97.75%, and 97.31%, respectively, and showed no significant differences among varieties. Ratios of removed rice bran after two times milling ranged 70.93-91.38%, with Dasanbyeo showing the highest ratio, and the average head rice ratio was 92.87%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.41-45
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• 2005

This experiment was carried out to identify the proper transplanting time at reclaimed saline land in the southwestern area of Korea from 2002 to 2004. The rice cultivars tested were Samcheonbyeo(Early maturing one), Nampyeongbyeo (Medium maturing one) and Hwaseongbyeo(Mid-late maturing one). The results are summarized as follows: No. of spikelet per the unit area was higher at transplanting on May 20 than those of the other transplanting time. when Samcheonbyeo was transplanted early, the ripened grain rate was high. But, Hwaseongbyeo and Nampyeongbyeo wasn't differ among transplanting time. The yield of milled and head rice(YMHR) was high transplanted May 20 in Samcheonbyeo, May 30 in Hwaseongbyeo, from May 20 to June 9 in Nampyeongbyeo. Among the varieties YMHR was higher in the order of Hwaseongbyeo, Samcheonbyeo and Nampyeongbyeo. There wasn't different of amylose and protein content among the transplanting time and varieties. But, palatability value was low transplanted early(May 20). Considering the rice growth, the rice good quality, the yield of milled and head rice, the proper transplanting time was May 20 to May 30 in Samcheonbyeo and Hwaseongbyeo, whereas Nampyeongbyeo was from May 20 to-June 9.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.88-93
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• 2005

The functional vice (Oryza sativa L.) has been highly regarded recently, in the change of rice maykets in the world. Goami2 (GA), one of the functional rice varieties, was developed from high-quality rice, Ilpumbyeo (IP). From the previous study, GA has been proved its beneficial effect on the improvement of metabolic control and body weight reduction especially in obesity, We could certain that GA was very difficult to be gelatinized due to the micro lump shown in the Scanning electron micrographs (SEM) photos. To improve its cooking quality, we investigated the changes of physicochemical properties, which were differentiated by the conditions of milling and blending. As GA was milled every $2\%$ until eliminating $12\%$, the nitrogen content was decreased linearly. But the decreasing rate of nitrogen content of GA during milling process was relatively lower than that of IP. Thus, we assumed that GA has relatively high nitrogen in inner starch of grain. The degree of milling had no effect on the gelatinization of cooked GA, but affected lightness and whiteness linearly, which were ranged in normal values when the rice was milled more than $10\%$ in weight. So we could concluded that the milling process was not proper to improve cooking quality of GA. And we could suggested that GA was needed to soak into water at least one hour before cooking by it water absorption rate at normal temperature$(21^{\circ}C)$ and sensory evaluation. From the texture analysis, cooked GA had higher hardness than other varieties. Therefore, we blended GA with IP, Baekjinju(BJ) and Hwasunchalbyeo(HS), then subjected to sensory evaluation. All evaluation items including the sensory preference were the highest scores for the rice blended with glutinous rice varieties, BJ and HS.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.375-379
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• 2007

This study was carried out to examine the effects of storage duration on physico-chemical properties of milled rice. Rough rice of three rice ecotypes(Japonica, Tongil and F1 hybrids with Tongil back-ground) was stored for 4, 16, 28 and 40 months without artificial environmental control in seed warehouse. And this materials were investigated for seed germination rate, brown rice hardness, alkali digestion value(ADV), contents of protein, amylose, total sugar, and reducing sugar. Seed germination rate was significantly reduced with storage duration increased regardless of rice ecotypes : 66.7% from 16 months storage, 2.5% from 28, and nil from 40 months storage in Japonica rices. And 54.0%, 67.9% in Tongil, and F1 hybrid after 40 months storage, respectively. Brown rice hardness was not significantly affected by storage duration but showed significant genotypic differences. As the storage duration prolonged, sugar content and alkali digestion value increased, protein content declined while amylose content did not show clear tendency. Total and reducing sugar contents showed sharp increase upto 16 months storage and thereafter steady in crease, and the percentage of reducing sugar content out of total sugar content increased with extended storage duration.

• Korean Journal of Environmental Agriculture
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• v.34 no.4
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• pp.303-308
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• 2015

BACKGROUND: Recently, various rice by milling degree is sold for health and taste. To provide safe food to consumers, it is need to know the change of heavy metal contents according to milling degree of rice.METHODS AND RESULTS: This study was to investigate residual the levels of cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) as stated in the milling degree of the rice contaminated Cd and Pb from 2011 to 2012 in Chungcheongnam-do. Rice samples exceeded the maximum residue limits (MRL) of Cd and Pb were milled by five degrees (0.0, 2.45, 8.02, 10.48, 15.09%). Milled rice was digested by microwave method, and analyzed heavy metal contents using ICP-OES. Recovery ratios of 4 heavy metals such as Cd, Pb, Cu and Zn were ranged for 79.7-98.9%, and limits of detection (LOD) and limits of quantitation (LOQ) were fulfilled with the normal analytical standards. Concentrations of Cd, Pb, Cu and Zn were ranged 0.416-0.433 mg/kg, 0.183-0.26 mg/kg, 3.639- 3.882 mg/kg and 16.868-19.801 mg/kg, respectively.CONCLUSION: From these results, conforming with increase of milling degree of rice, Cd, Pb, Cu, and Zn contents tended to decrease. The contents of heavy metals were decreased 3.1% in Cd, 29.3% in Pb, 6.4% in Cu and 15.1% in Zn, in according to the highest milling degree of 15.09%.