• Journal of the Korean Professional Engineers Association
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• v.2 no.6_7
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• pp.12-23
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• 1969

The purpose of this study is to find out the reasonable amount of evapo-transpiration required for the paddy rice plant during the whole growing season. So, on the basis of the 3year experimental data concerning the evapo-transpiration from 1966 to 1968, the author obtained the following results. 1) The leaf area index in the densely planted plot is generally higher than that in the conventionally planted one during the first half of growing season. So, the coefficient of transpiration in the former plot is some what higher than in the latter, and the coefficient of water surface evaporation under the plant cover has the inverse relation between both plots. 2) It is unreasonable that coefficient of evapo-transpiration is applied to the calculation of the evapo-transpiration requirments of each growing stage, because a certain degree of variation in meteorological factors and in the thickness of the plant growth is involved in it. 3) It is most reasonable that the rate of transpiration and of the water surface evaporation is applied to the calculation of the transpirated amount and evaporated one in each growing stage because it shows almost constant value in spite of any meteorological conditions in so far as the variety of rice, planted density and control of applying fertilizer are same and the disease and blight are negligible. 4) The ratio of the amount of transpiration to the weight of the whole air dried yields has the tendency of decreasing as that of the yields increase, having almost constant value despite the amount of pan evaporation; and the value is about 210 when the weight of root parts is included to that of the yields. 5) Although the required amount of transpiration during the whole growing season can be calculated with the above ratio, fig. 7 showing the relation between the amount of transpiration and the weight of the yields is more reasonable and will be convinient to find it. And the requirements of water surface evaporation during the same season can also be directly found with the weight of air dried straw refering to fig.8.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.522-527
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• 1997

To find out the optimum seeding rate in corrugated water seeded rice, field experiment was carried out at Yeongdeog Substation of the National Yeongnam Agricultural Experiment Station for two years, 1994 and 1995. A rice cultivar Donghaebyeo, was seeded on May 15 with five seeding rate from 3kg /10a to 7kg /10a. The number of seedling stand per unit area was curvilinearly increased with seeding rate. In characteristics of rice plant associated with lodging, the plant height, fresh weight per tiller, Culm wall thickness and ratio of gravity center were not significantly different among seeding rates, but the breaking strength of 4th internode was slightly decreased with increasing seeding rate and thus, lodging index was generally greater at higher seeding rate than lower seeding rate. Field lodging was observed at 1~3 degree in seeding rate of 5~7kg /10a. Panicle number per unit area was generally increase with increase of seeding rate, while ratio of ripened grain was decreased with increase of spikelet number. Milled rice yield was curvilinearly increased with seeding rate. The optimum seeding rate in the highest rice yield was 4.8kg /10a in 1994, and 4.3kg /a in 1995, respectively.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.150-154
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• 1990

Various sterilization temperatures $(110^{\circ}C,\;120^{\circ}C,\;130^{\circ}C)$ and air volumes (air, 31ml, half-vacuum; 13ml, vacuum; -0.7ml) within the retort pouch were tested for the development of the simple retort rice processing techniques in which the pouch were filled with rice and water, and then sterilized. Water content of retort rice was found to be 59.0-63.3% resulting from mixing the rice and water in the ratio of 1:1.1. The most uniform water content was obtained from retort rice sterilized at $130^{\circ}C$ and packaged under vacuum. The larger water content differences were observed with the increase in internal air volumes within the retort pouch. Spreading degree of retort rice was geater than that of general cooked rice, was lower in upper layer than in low layer, and became lower with the larger air volume and higher sterilization temperature. a degree of rice became higher with the Increase of sterilization temperature but that was not affected by the internal air volume of the pouch. The higher sterilization temperature and the lower the air volume, the higher the whiteness was. The highest whiteness was obtained by packaging under vacuum and sterilizing at $130^{\circ}C$. Intact degree was much higer in packaging under air than vacuum. In sensory evaluation the retort rice of vacuum pack was good in color and spreading degree but not in appearance because of blocking and deforming, but that of air pack was good in texture on the contrary. The best quality was obtained by packaging under half-vacuum and sterilizing at $130^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.452-457
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• 2009

The objective of this study was to provide fundamental data on breeding cultivar and cultural technique to identify quality characterization according to damage degrees in rice when are damaged at low temperature. For induction of cold damage, we treated the irrigation water at $17^{\circ}C$ from the panicle formation stage to the heading date. The rice products were harvested by grades according to the sterility ratio and investigated 5 items of quality analysis including ripened grain ratio, brown/rough rice ratio, 1000 grain weight of brown rice, protein content, and amylose content. The quality analysis were characterized by each items according to the sterility ratio. As a result, the ripened grain ratio was y=1.0444x-7.6597($R^2=0.9874^{**}$), protein content was y=-0.046x+10.875 ($R^2=0.6973^*$), and head rice ratio was y=-0.2306x+104.32 ($R^2=0.634^*$), but the amylose content, brown/rough rice ratio and the milled/brown rice ratio were not significant. The rice plants, which injured by the low temperature, had bad influence in the yield and quality. Consequently, the breeding of rice cultivar and development of cultural technique are required to improve its cold tolerance.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.589-601
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• 2011

The purpose of this study was to investigate changes in the cooking process of $Pat-juk$(red beans porridge), $Jat-juk$(pine-nut porridge) and $Tarak-juk$(milk porridge) in cooking books published after Korean modern era, approximately from late 19th century to the present. We analyzed 11 historical cook books were analyzed. It is found that the amount of red beans used for $Pat-juk$ was the same or more than that of rice but never less than rice. Only one cook book suggested sugar as seasoning for final taste, but all the other cook books mentioned salt for final taste. $Hangukeumat$(1987) suggested the method for obtaining optimum color for $Pat-juk$. After smashing and passing through the cooked red beans, collecting the red bean water to boil first and then adding the passed through red beans to boil together, in which rice will be added the last to be boiled. For $Jat-juk$, the ratio of the amount of pine-nut and rice were varied among cook books that the amount of pine-nut can be more, same or less than rice. $Jat-juk$ can have salty or sweet, so sugar, honey or salt were used for final seasoning. Pine-nut and rice were cooked together or cooked successively depending on cook books. The changes in cooking procedures of $Tarak-juk$ were the portion of milk used and the method of preparing rice before making the porridge. Firstly, the portion of milk increased over time. $Tarak-juk$ can be also tasting both sweet or salty, so sugar or salt was used for final seasoning. Secondly, two method of preparing rice were found; one is that rice was ground after soaking in water and the other is that rice was ground and toasted before putting into the porridge. When the ground rice was toasted, the milk was added with water at the same time because the cooking time of the porridge with toasted rice was shortened so that the milk could be added earlier than the other method without the risk of sticking on the bottom of the pot. In further studies, the cooking procedures used in the previous period of the late 19th century should be examined. Also after restoring all the cooking methods suggested in cook books, the comparison of the sensorial and nutritional value needs to be carried out for applying or reinventing new recipe for food industry.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.475-478
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• 2002

Post-harvest treatment for barley production requires many steps including drying, cleaning, and packing, and these steps be needed many labor input. Rice processing complex (RPC) is useful for post harvest management system in rice production. However, it is rare to be used for barley production. This study was conducted to explore the variations of quality and labor saving between conventional method and bulk-management system in post-harvest using RPC. The sorting rate was not different between manual method and bulk management. The hardness of non-polished grain was ranged 10,175-10,329 g/$3.14mm^2$, and that for non-polished grain was higher than that for polished grain, but there was not different between drying method. There was not be showed the hunter's value such as L, a and b according to drying method. Cooking characters such as water absorption ratio, swelling ratio, and water soluble extracts by circulated or continued dryer was higher than manual drying using solar heat. Labor input per ha for each cultivation process in bulk-management of barley using rice processing complex was 21 hours, compared to 46 hr/ha in the conventional method, labor input was greatly saved by up to 54.3% in the post-harvest bulk management system.

• Korean Journal of Microbiology
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• v.6 no.4
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• pp.113-121
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• 1968

This study has been aimed to determine the ecological factors with relationship to the Jongkok production in view of fermentation technology by means of some strains, Asp. kawachii, which is now preserved by the author and the following factors are included during the study; inorganic salts, nitrogen, sugar, water contents and temperature. The results, are as follows: (a) Sugar among other above-mentioned factors is increasingly affecting the number of the short type of conidiophore on culture medium and the conidiophore is increased by direct ratio until glucose concentration of 50%, at which concentration is mostly effective for the short type of conidiophore, while other factors did not affect on it. (b) Until glucose concentration of 50% sugar component of culture medium is favorable for the spore formation of Asp. kawachii by direct ratio. And peptone or asparagine on nitrogen medium, calcium-phosphate among other inorganic salts, wheat bran and rice branare also favorable, but other factors rientioned earlier show no relationship with the spore formation. Sugar, however, also related with the spore color clearness of crimson and light brown, and spore color is mostly clear at the point of glucose concentration until 50%. And asparagine on nitrogen medium, calcium phosphate among other inorganic salts, rice bran did all affect on the color clearness, while other factors did not concern with color clearness. (c) Water, sugar and temperature have related with the acid formation which is promoted, by direct ratio at the point of water-saturated condition and glucose concentration of 50%, while temperature at $25^{\circ}C$favorably affected on the acid formation which is increased by inverse ratio at the temperature$25^{\circ}C$ to $45^{\circ}C$ And pH did not relate with the acid formation. (d) Cylindrical plate method devised by the author is mostly favorable for the preservation and isolation of culture, compared with the traditional slant medium method.

• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.848-854
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• 2011

The objective of this research was to experimentally test the effect of rice straw mats on the reduction of runoff, sediment and discharge under a laboratory scale with different rainfall intensity and slopes. We used the small runoff plots of $1m{\times}1m{\times}0.65m$ ($L{\times}W{\times}H$) in size were filled with loamy sand. Experimental treatments were bare (control), rice straw mats + PAM(SP), rice straw mats + PAM + sawdust(SPS) and rice straw mats + PAM + rice husks(SPR); slope of 10% or 20%; and rainfall intensity of 30 or 60 mm/hr. Runoff volume and coefficient from covered plots were significantly lower than those from control plots. Under the 30 mm/hr and 10% simulations, average runoff coefficient of covered plots decreased more than 92%. Under 60 mm/hr and 20% simulations, the ratios were between 39.8~58.1%. Under the condition of 30 mm/hr rainfall and 10% slope, sediment discharge from covered plots was practically zero. And at 20% plots, sediment reduction ratio was more than 95%. Under the condition of 60 mm/hr rainfall, sediment reduction ratio of 10 and 20% plots ranged between 86.3~95.3% and between 79.8~86.5%, respectively. The differences in initial runoff time, runoff and sediment discharge among different cover materials were not significant. Rainfall intensity showed higher impact on initial runoff time, runoff, and sediment discharge than slope. It was also shown that even if runoff reduction by surface cover were low, sediment discharge reduction could be very significant and contribute to improve the water quality of streams in sloping agricultural regions. It was concluded that the use of straw mat and PAM on sloping agricultural fields could reduce soil erosion and muddy runoff significantly and help improve the water quality and aquatic ecosystem in receiving waters.

• Food Science and Preservation
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• v.14 no.5
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• pp.504-510
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• 2007

An extrusion process was to make an onion kimchi snack from rice grit and onion kimchi powder, in an effort to enhance the nutritional value, flavor, and physicochemical properties of the extrudate. This study investigated optimum conditions (moisture content, barrel temperature, and the content of onion kimchi powder) for the production of high-quality rice extrudate products, and measured quality properties (water absorption index, texture, expansion ratio, and color) of rice extrudate to which onion kimchi powder had been added. Onion kimchi powder at 3%, 5%, 7%, and 10% (all w/w) was mixed with rice grit and the mixture then extruded in a twin-screw extruder. The texture of onion kimchi mack became softer as onion kimchi powder level rose, and water absorption ability increased. The expansion ratio and the lightness of extrudates decreased with increases in onion kimchi powder levels. The maximum water absorption index am the minimum hardness were obtained with 10% onion kimchi powder. Rice extrudate with 10% onion kimchi powder was suitable for extrusion cooking md obtained the highest score for overall acceptability by sensory evaluation.

• Korean journal of food and cookery science
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• v.2 no.2
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• pp.43-54
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• 1986

Back-pyun is a kind of rice cake made by steaming rice flour added sugar, water and salt and garnished with shredded chestnuts, dates, mushrooms and pinenuts. The Back-pyun has been widely used in Korean celebrations. This study aimed to compare and determine the effects on sensory characteristics and texture of Back-pyun 1) when the proportion of glutinous rice, added i.1 making Back-pyun, is 0%, 5%, 10%, 15%, 20%, 25% and 30% 2) then it reheated after storage for 0,24, 48 and 72 hours. Evaluation was conducted through sensory evaluation and objective evaluation. The results are as follows : 1. In sensory evaluation, color of Back-pyun turned yellow as the addition level of glutinous rice increased and then by reheating after storage for 24, 48 and 73 hours. Coarseness was not significantly different as the addition level of glutinous rice increased before storage. But Back-pyun reheated after storage for 24,48 and 72 hours were significantly different by the addition level of glutinous rice. Softness, dryness and crumblyness tended to decrease as the addition level of glutinous rice increased and by reheating after storage for 24, 48 and 72 hours. The most favorite tendency on the appearance was at the addition level of glutinous rice of 5%. Texture and overall preference were better at the addition level from 10% to 20% than any other levels. 2. Rheometer measurement indicated that compression force, gumminess ana chewiness tended to increase as the addition level of glutinous rice increased and decrease by the storage conditions. But work ratio and recovered height did not have much effect the addition level of glutinous rice and the storage conditions. Compression force of Back-pyun (not reheated) tended to increase by the storage time and the addition level of glutious rice. Especially it showed remakably increasing tendency during 24 hours storage (at $4^{\circ}C$) 3. Moisture content tended to increase by the addition level of glutinous rice and decrease by the storage time. But moisture content of Back-pyun reheated after storage for 24 hours stowed the increasing tendency. 4. Softness of Back-pyun had significant relationship with compression force and work ratio. Dryness and crumblyness had significant relationship with work ratio. Therefore compression force and work ratio represented the texture of Back-pyun.