• Korean Journal of Food Science and Technology
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• 제21권5호
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• pp.613-618
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• 1989

Tirteen rice varieties of Japonica-Indica briefing type (J-I breeding type) and ten of Japonica type produced in Korea in 1985 were studied on cooking quality of milled rice and texture of cooked rice. The results are as follows: in the Looking quality, water uptake ratio of cooked rice and total solid in residual liquid showed significant $(p<2.172^*\;and\;2.419^*,\;respectively)$ between J-I breeding type and Japonica type The water uptake ratio of cooked rice was higher J-I breeding type than Japonica type but the total solid and intensity of iodine blue value in residual liquid were lower J-I breeding type than Japonica type. Minimum cooking time of milled rice showed significant $(p<2.375^*)$ between J-I breeding type and Japonica type for texture of cooked rice. The cooking time of J-I breeding type shorter than Japonica type. Hardness and cohesiveness in texture of cooked rice appeared to be significant cant $(p<4.370^{***}\;and\;2.371^*,\;respectively)$ between J-I breeding type and Japonica type, and then hardness was higher Japonica type than J-I breeding type, but cohesiveness was lower Japonica type than J-I breeding type. The correlation coefficients between amylose content and adhesiveness of varieties in the same type was $-0.922^{**}$ in J-I breeding type and $-0.915^**}$ in Japonica type. The correlation coefficients between protein content and hardness of the varieties in the same type was $0.954^{**}$ in Japonica type and so denoted as positive correlation. And the scatter diagram between protein and hardness could be divided into J-I breeding type and Japonica type.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제46권3호
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• pp.236-240
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• 2001

The lysimeter experiment was conducted to investigate the temporal changes of irrigation requirement, soil water percolation and rice root distribution during rice growing period under different soil texture that were sandy loam, clay loam and clay paddy soil in 1999 and 2000. The irrigation requirement in the first year was 3,306 l/$m^2$ in clay loam, 2,650 l/$m^2$ in sandy loam and 2,002 l/$m^2$ in clay soil. However, the highest irrigation requirement was 5,281 l/$m^2$ in sandy loam and the next was 4,984 l/$m^2$ in clay loam and 3,968 l/$m^2$ in clay soil in the second year, Soil water percolation in the first year was 2,141 l/$m^2$ in clay loam, 1,228 l/$m^2$ in Sandy loam and 862 l/$m^2$ in clay soil. However, in the second year, the highest water percolation of 4,448 l/$m^2$ was measured in sandy loam, and was followed by 3,833 l/$m^2$ in clay loam and 2,925 l/$m^2$ in clay soil. Distribution ratio of rice roots measured in 0-10cm of soil depth was 56.0% in sandy loam, 61.4% in clay loam and 72.1% in clay soil, respectively. It was interpreted that the greater water percolation measured in the second year was caused mainly by the large amount of rice root growth. Therefore, it was concluded that the soil water percolation in rice paddy soil was affected greatly not only by soil texture but also the growth of rice root.

• Journal of The Korean Society of Agricultural Engineers
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• 제61권6호
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• pp.93-101
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• 2019

This study aims to analyze the influences of applications of two different evapotranspiration (ET) estimation methods on the irrigation water requirements (IWR) for paddy rice and water supply reliability of agricultural reservoirs. The modified Penman (MP), traditional method, and the Penman-Monteith (PM), the new adopted method, were applied on 149 reservoirs located in Honam province for this study. The weather date was used from 1987 to 2016, and analysed the trends of temperature and rainfall during rice growing season between past and current 10 years respectively. The increased average temperature and rainfall were observed from the current 10 years compared to the past years. This phenomena impacts on the results of ET and IWR estimations with decreased IWR obtained from high rainfall regions and increased ET obtained high temperature regions. For the comparisons of application results of two ET approaches, the PM method showed lower ET and IWR, and hence more reliable storage capacity of the reservoirs respect to water supply to paddy fields. The results also showed that the influences of different ET methods applications on the water supply reliability of reservoirs are negligible for the cases of over 3.7 watershed ratio and 670 mm unit reservoir storage, while significant variations of the results obtain from the applications between two ET approaches for the opposite cases. Further studies are necessary to consider various field conditions for practical applications of the PM method estimating ET in the fields of paddy farming.

• Korean Journal of Plant Resources
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• 제19권6호
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• pp.687-691
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• 2006

This experiment was conducted on rice (cv. 2005 Thaoi) seeds to study whether priming with deep sea water (DSW) results in enhancement of seed emergence and seedling growth and to identify the optimum concentration of Deep Sea Water (DSW) for priming. Two experiments were conducted subsequently. In experiment 1, four concentrations of the DSW (10%, 20%, 30% and 40%), and in experiment 2, five concentrations of DSW (10%, 15%, 20%, 25% and 30%) were prepared and seeds were primed for 24 hours duration at $25^{\circ}C$. Beside this, hydro priming with plain water was also included as a control. Experiments were laid out in Completely Randomized Design (CRD) with three replications. Result showed that 20% DSW seed priming treatment had improved the emergence, seedling height, number of roots and root length as compare to other with DSW or without DSW treatments. Beyond 20% DSW priming (i.e. 25%, 30% and 40%) were not suitable for priming the seed. On the basis of seedlings growth parameters; emergence, seedling height, root number and length, and shoot root ratio, 20% DSW priming was the best priming treatment.

• Magazine of the Korean Society of Agricultural Engineers
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• 제13권4호
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• pp.2439-2444
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• 1971

This experiment is conducted to see the alteration in calculation of amount of duty of water in paddy fields, by the miraculous rice TONG-IL(IR667) made its appearance to us, therefore results obtained were summarized as follow. 1. In comparison with depth of evapo-transpiration and evaporation in the evaporator, the ratio is ET/V=1.84 in clay loam and ET/V=2.00 in loam, the value is larger than any vairety. 2. Comparison by growing periods of rice plants growing period 5 and Ear for mation stage (primor stage) 6 ET/V value grow larger from 3.30 to 3.77. 3. Transpiration ratio is 260.4 in clay loam and 275.0 in loam, two value are less than 300.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제51권spc1호
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• pp.119-124
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• 2006

This study was carried out at the Chuncheon Substation, National Institute of Crop Science to determine the effect of cold water irrigation on the milling and polished quality of rice, as well as its physicochemical and amylogram characteristics, and palatability Chilling by Irrigation of cold water $(17^{\circ}C)$ induced delay of days to heading, reduction of culm length, inferiority of panicle exsertion and high sterility of panicle. Head rice ratio was decreased, while the percentage of chalky and creak rice increased with increasing sterility over from 20%. Protein content was gained 0.9-2.0% more than, while whiteness and palatability of the milled grain were reduced under cold water irrigation treatment. Significant decrease in maximum viscosity and breakdown viscosity of rice flour was investigated under cold water treatment by amylogram analysis, while the initial gelatinization temperature and setback viscosity were increased. Sensory panel test showed that the palatability of cooked rice was unfavorable and its stickiness was lower compared with that under normal condition. Differences in the aroma of cold-treated and untreated cooked rice were not performed significantly.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 한국에너지공학회 2003년도 춘계 학술발표회 논문집
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• pp.431-435
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• 2003

Because the Tissue Bound Tritium of food irradiates the organic tissues of a man during a longer time than the Tissue Free Water Tritium, we found the ratio of labile and bound hydrogen, which is the direct source of TBT concentration, in grain such as rice and barley. Tissue free water was extracted from rice and barley sampled, adjacent to Wolsung nuclear power plants of CANDU type, by freeze-drying. Tissue bound water was taken from some of the dried samples by high-pressure combustion. The other of the samples was washed by tritium-free water for 2-3 hours, and dried again by freeze-drying. Tissue bound water was taken again from some of the second dried samples by the combustion. The extracted tissue free and bound waters were distilled and TFWT and TBT concentrations of them were counted by a liquid scintillation counter. Through alternating washing, drying and combustion until the concentration of TBT would be constant, the tritium concentration existing as bound hydrogen was found. The ratios of labile and bound hydrogen of rice and barley were determined by TR concentration, initial TBT concentration and bound tritium concentration. The ratios of bound hydrogen of rice and barley were 0.55, 0.60 relatively.

• Korean Journal of Food Science and Technology
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• 제34권2호
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• pp.225-231
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• 2002

The physicochemical characteristics of pine nuts gruel were investigated to find the effects of processing condition during the processing. Three-dimensional response surface methodology was applied to investigate effects of ratio of water volume and pine nuts weight to rice weight and heating time on dependent variables of the physicochemical characteristics. The dependent variables in physicochemical characteristics were viscosity (cP), spreadability (cm), pH, soluble solid content (%), color, total sugar (%) and amylose content (%). The F-value of ratio of water volume and pine nuts weight to rice weight and heating time to viscosity were 8.91, 4.54 and 5.02 respectively and they are significantly different at 5% level. The F-value to spreadability were 5.44, 7.88 and 8.04 respectively and they are significantly different at 5% level. These results suggest that water volume, pine nuts weight and heating time greatly affect the viscosity and spreadability of pine nuts gruel. The processing condition also affect the soluble solid content. The changes of the processing condition did not affect the pH of pine nuts gruel. We found that the L, a, b value were affected more by ratio of water volume and pine nuts weight to rice weight than by heating time. The water volume affected more the total sugar and amylose content of pine nuts gruel than pine nuts weight and heating time.

• Korean Journal of Food Science and Technology
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• 제26권4호
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• pp.442-447
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• 1994

Effect of different mixing ratio of non-glutinous and glutinous rice on physical and rheological properties of extrudate prepared in a single screw extruder were examined. The extrusion conditions in term of screw speeds, moisture content and die temperature were 258 rpm, 18% and $120^{\circ}C$, respectively. The resisdence time distribution of the most of materials were within 30 second and small portion of them went up to 80 second. The expansion ratio was the highest value (2.93) for 70% of glutinous rice in the mixture, while the lowest value for 100% of non-glutinous rice. Breaking strength was in the range between 1,051g and 1,117g for $10{\sim}20%$ of glutinous rice in the mixture, while the lowest value (737g) for 80%r of glutinous rice. As the amount of glutinous rice increased, L and a values were increased and b value was decreased. The uncooked cold paste viscosity had 400 B.U. for 100% non-glutinous rice , while no peak for the 100% glutinous rice. As the amount of glutinous rice increased up to 100%, the water absorption index (WAI) was decreased, while water solubility index (WSI) was increased. The rheological properties of extrudate were accounted by the law of Oswald. The flow behavior index of extrudate was less than 1.0, which showed pseudoplastic behavior. Yield stress was the highest value for 20% of glutinous rice in the mixture and the lowest value for $80{\sim}100%$ of glutinous; rice. Number of air cell was between 128 and 159 for $80{\sim}100%$ of glutinous rice in the mixture, while $81{\sim}84%$ for $0{\sim}20%$ of glutinous rice. The degree of shapefact was increased more when the mixtures of glutinous and non-glutinous rice was used than when glutinous or non-glutinous rice was only used.

• Applied Biological Chemistry
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• 제28권2호
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• pp.62-67
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• 1985

Hydration rate of 35 Japonica and 24 J x Indica rice varieties at $23^{\circ}C$ was investigated and an attempt was made for a tentative classification of milled rice into six groups based on hydration rate. Each rice variety had characteristic value for hydration rate. In general, J x Indica rice hydrated at a faster rate than Japonica rice. Hydration rate was negatively correlated with the ratio of length to width of rice grain. No correlation was found between hydration rate and protein, amylose, surface area, volume or initial water grain.