• Korean Journal of Materials Research
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• v.22 no.6
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• pp.321-327
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• 2012

The production of functional activated carbon materials starting from inexpensive natural precursors using environmentally friendly and economically effective processes has attracted much attention in the areas of material science and technology. In particular, the use of plant biomass to produce functional carbonaceous materials has attracted a great deal of attention in various aspects. In this study the preparation of activated carbon has been attempted from rice husks via a chemical activation-assisted microwave system. The rice husks were milled via attrition milling with aluminum balls, and then carbonized under purified $N_2$. The operational parameters including the activation agents, chemical impregnation weight ratio of the calcined rice husk to KOH (1:1, 1:2 and 1:4), microwave power heating within irradiation time (3-5 min), and the second activation process on the adsorption capability were investigated. Experimental results were investigated using XRD, FT-IR, and SEM. It was found that the BET surface area of activated carbons irrespective of the activation agent resulted in surface area. The activated carbons prepared by microwave heating with an activation process have higher surface area and larger average pore size than those prepared by activation without microwave heating when the ratio with KOH solution was the same. The activation time using microwave heating and the chemical impregnation ratio with KOH solution were varied to determine the optimal method for obtaining high surface area activated carbon (1505 $m^2$/g).

• Journal of the East Asian Society of Dietary Life
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• v.11 no.4
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• pp.235-246
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• 2001

The survey on the practice of the memorial ceremonial food in Chuncheon area showed it varied according to social position of officiator, location(inland or seaside town) , and personal condition. The study included the foods prepared for the memorial services on the memorial day. New Year's Day and Chusok. 1. 40.4% of the subjects were in the thirties at their age, 46.6% were high school graduates, 57.3% were the first daughter-in-law, 40.4% had no religion, 30.9% were working at public administration and earned less than 1 to 1,5 million won monthly. 2. 71.7% of the subjects who replied that the ancestor worship service had to be kept were Buddhists. 55.4% of them were high school graduates, and 58.8% of them ran independent businesses. They learned how to practice the ancestor worship service from their mother before marriage or from their parents-in-law after marriage. 3. The older the officiators, the better they wanted to keep the traditional format of the service, but the Christians and Catholics wanted to change the format to western style in the future. 4. 92.7% of them served cooked milled rice. They prepared the soup in the order of beef soup, radish soup and dried Alaskan pollack soup. 5. Among cooked vegetable dishes, bracken was used the most and balloonflower root, mung bean sprout and spinach followed. Among jeon(pan-fried foods). frozen Alaskan pollack was used the most and buckwheat, mung bean and meatball followed. 6. They served san-juk(beef kebab) mostly on the ceremony. Among the grilled foods, tofu was the favorite, and croaker followed. 7. Among the fried foods. squid was the favorite, and sweet-potato and shrimp followed. Among the dried foods. they used in the order of dried Alaskan pollack, dried beef and squid. 8. Among the rice cake and traditional confectionery, they used in the order of Yak-sik(sweet rice cake), Gang-jeong(fried glutinous rice cookie), Jeol-pyun and In-jeol-mee. Among a beverage, they served Sik-hye(fermented rice drink) mostly. 9. Among fruits, apples. jujube, chestnut and dried persimmon were served. Aong a liquor, Cheongju was served mostly. 10. Soy sauce, salt and salted fermented fish were served, too.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.221-225
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• 2002

This study was conducted to identify the effects of slow release fertilizer (LCU) on ridge direct seeding on dry paddy of rice as an irrigation water-saying cultural system. During 1999-2000, a series of experiments was carried out at field (Chonbuk series) of the National Honam Agricultural Experiment Station, RDA using Dongjinbyeo. Plant height and culm length during the total growth duration were the longest and panicle umber per $m^2$ was the highest in 100% LCU application rate. Leaf area index and top dry weight were the highest in the 100% LCU application rate. They increased as more LCU was applied. Nitrogen uptake was the highest in 100% LCU application, and N use efficiency was the highest in LCU 60% + FP (fertilization at panicle formation stage) 20% application. Milled rice yield was 7% higher in 100% LCU application rate than that of conventional N application. Ripened grain rate and 1,000-grain weight of brown rice did not differ, but panicle number per $m^2$ and grain number per m2 were the highest at 100% LCU application.

• Journal of Crop Science and Biotechnology
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• v.10 no.1
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• pp.33-38
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• 2007

Nitrogen management at the panicle initiation stage(PI) should be fine-tuned for securing a concurrent high yield and high quality rice production. For calibration and testing of the recommendation models of N topdressing rates at PI for target grain yield and protein content of rice, three split-split-plot design experiments including five rice cultivars and various N rates were conducted at the experimental farm of Seoul National University, Korea from 2003 to 2005. Data from the first two years of experiments were used to calibrate models to predict grain yield and milled-rice protein content using shoot fresh weight(FW), chlorophyll meter value(SPAD), and the N topdressing rate(Npi) at PI by stepwise multiple regression. The calibrated models explained 85 and 87% of the variation in grain yield and protein content, respectively. The calibrated models were used to recommend Npi for the target protein content of 6.8%, with FW and SPAD measured for each plot in 2005. The recommended N rate treatment was characterized by an average protein content of 6.74%(similar to the target protein content), reduced the coefficient of variation in protein content to 2.5%(compared to 4.6% of the fixed rate treatment), and increased grain yield. In the recommended N rate treatments for the target protein content of 6.8%, grain yield was highly dependent on FW and SPAD at PI. In conclusion, the models for N topdressing rate recommendation at PI were successful under present experimental conditions. However, additional testing under more variable environmental conditions should be performed before universal application of such models.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1742-1748
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• 2014

This study investigated the quality characteristics of commercial rice flour (CRF) and rice flours prepared by different milling methods for sulgidduk. For particle distribution, dried rice flour after the 1st roll mill using a pin mill showed a particle size of greater than $710{\mu}m$, whereas a particle size less than $250{\mu}m$ accounted for 48% of whole rice flour. This proportion was higher than CRF after the 2nd step roll mill. Crude protein, lipid, and ash contents were significantly highest in 1st roll mill samples. For color, roll & pin made up of many small particles showed a high L value. CRF and roll & pin showed significantly higher starch damage and water-holding capacity, whereas pasting temperature, peak viscosity, and setback of RVA pasting characteristics were lower than 1st roll mill. When rice cakes were made from three kinds of rice flour, roll & pin was not significantly different compared to the CRF. However, rice cakes made with 1st roll milled rice flour showed rough crumb and crust. Rice cake made with roll & pin or CRF showed similar characteristics for texture. In the quantitative descriptive analysis, rice cake made with roll & pin showed better appearance, flavor, taste, texture, and overall acceptability than CRF and 1st roll mill. Therefore, rice flour prepared by roll & pin could be applied to sulgidduk with high quality.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.436-440
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• 2012

This study was carried out to find optimal rice varieties and selection index for sushi. The suitability tests about appearance and palatability were conducted by 31 professional sushi chefs and the physicochemical and pasting properties of the selected 7 rice varieties (Koshihikari, Dami, Deuraechan, Boramchan, Juanbyeo, Sindongjin and Hopum) of milled and cooked rice were evaluated. According to the adaptability for sushi shape and taste of rice, Hopum and Sindongjin showed more suitable appearance and taste than others. Also, they showed remarkable pasting properties similar to Koshihikari which is widely known as a suitable for sushi. In the relationship between suitability and pasting properties for sushi, peak viscosity and breakdown viscosity showed highly positive correlation, and setback viscosity showed negative correlation. These results suggest that pasting properties can be applied to select the suitable varieties for sushi.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.08a
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• pp.57-74
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• 2005

Rice yield and protein content have been shown to be highly variable across paddy fields. In order to characterize this spatial variability of rice within a field, the two-year experiments were conducted in 2002 and 2003 in a large-scale rice field of $6,600m^2$ In year 2004, an experiment was conducted to know if prescribed N for site-specific fertilizer management at panicle initiation stage (VRT) could reduce spatial variation in yield and protein content of rice while increasing yield compared to conventional uniform N topdressing (UN, ,33 kg N/ha at PIS) method. The trial field was subdivided into two parts and each part was subjected to UN and VRT treatment. Each part was schematically divided in $10\times10m$ grids for growth and yield measurement or VRT treatment. VRT nitrogen prescription for each grid was calculated based on the nitrogen (N) uptake (from panicle initiation to harvest) required for target rice protein content of $6.8\%$, natural soil N supply, and recovery of top-dressed N fertilizer. The required N uptake for target rice protein content was calculated from the equations to predict rice yield and protein content from plant growth parameters at panicle initiation stage (PIS) and N uptake from PIS to harvest. This model equations were developed from the data obtained from the previous two-year experiments. The plant growth parameters for this calculation were predicted non-destructively by canopy reflectance measurement. Soil N supply for each grid was obtained from the experiment of year 2003, and N recovery was assumed to be $60\%$ according to the previous reports. The prescribed VRT N ranged from 0 to 110kg N/ha with average of 57kg/ha that was higher than 33kg/ha of UN. The results showed that VRT application successfully worked not only to reduce spatial variability of rice yield and protein content but also to increase rough rice yield by 960kg/ha. The coefficient of variation (CV) for rice yield and protein content was reduced significantly to $8.1\%\;and\;7.1\%$ in VRT from $14.6\%\;and\;13.0\%$ in UN, respectively. And also the average protein content of milled rice in VRT showed very similar value of target protein content of $6.8\%$. Although N use efficiency of VRT compared to UN was not quantified due to lack of no N control treatment, the procedure used in this paper for VRT estimation was believed to be reliable and promising method for managing within-field spatial variability of yield and protein content. The method should be received further study before it could be practically used for site-specific crop management in large-scale rice field.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.82-89
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• 2000

Relationship among the properties of rice, such as amylose contents of endosperm starch, sugar content and amylogram characteristics, and processing properties for rice bread was studied. The amylose content of the rice cultivars decreased in order of Nampungbyeo, Whachungbyeo>Punchilmi(fl)>Nampung CB243> Whachung du-I, Nampung EM90>Whachung-chalbyeo>shr. Protein contents of rice tested in this study were almost same level, however, shr, the high sugar rice, showed the highest protein content scored as 8.2%. The study showed that the amylose contents of rice cultivars were negatively correlated with their protein contents. The starting temperatures for gelatinization of the flour of Punchilmi(fl) and Shurunken(shr) were low, however, in case of Whachungbyeo and Nampungbyeo plus their mutants derived from the both, the stickiness and the hardness of the flours were shown to be positively correlated with the amylose contents. In addition, loaf volume tested using sensory evaluation and overall quality showed the same tendency. Among the rice cultivars tested in this study, breads made from white rice had good qualities in bread making process than those made from brown rice. The bread made from Nampungbyeo was demonstrated to have highest score e in overall quality, as well as the lowest retrogradation index during storage at $4^{\circ}C$

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.184-192
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• 2017

Rice flours from five rice (Oryza sativa L.) varieties with different amylose content were prepared by both wet and dry milling processes. The moisture content of wet-milled rice flours (WMR) was approximately three-times higher than that of dry-milled rice flours (DMR). Water absorption index (WAI), water solubility index (WSI), and swelling power (SP) increased in proportion to temperature. The WAI, WSI and SP values of DMR were higher than those of WMR. Baeokchal (BOC), which is a waxy rice cultivar, had a significantly high WSI value. Pasting properties of DMR, except for the BOC cultivar, resulted in an increase in peak, trough, final, and setback viscosities. The levels of resistant starch in four cultivars, except for Dodamssal (DDS), were under 1%, irrespective of the milling process, whereas the resistant starch contents of DMR and WMR in DDS were 9.18% and 6.27%, respectively. In vitro digestibility of WMR was higher than that of DMR, and the estimated glycemic index of the rice flour varieties ranged from 57.6 to 81.3. Damaged starch content of WMR was less than that of DMR; in addition, a negative correlation was observed between the amylose and damaged starch contents of WMR. These results suggest that the properties of rice flour vary depending on the milling method and flour variety, and could be a reference for selecting the appropriate processing method.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.611-615
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• 2011

'Manjong' is a new japonica rice cultivar developed in 2009 derived from a cross between 'Yeongdeog34' and 'Nampyeongbyeo' at the Department of Functional Crop, NICS, RDA. This cultivar is suitable for the double cropping system after the cash crop cultivation. Heading date of 'Manjong' is later than 'Keumobyeo' under the late transplanting cultivation on July 10. It has high grain fertility under cold conditions and low premature heading. One of the distinguishing characteristics of this variety is its resistance to major diseases like leaf blast and rice stripe virus disease. However, it shows susceptibility to major insect pests and bacterial blight disease. Milled rice kernels are translucent with non-glutinous endosperm and have 7.2% protein and 18.7% amylose contents. Ripening ratio and head rice ratio is very higher than those of 'Keumobyeo'. The palatability of cooked rice is also better than 'Keumobyeo'. The milled rice yield of 'Manjong' in local adaptability tests after harvest of the cash crop is $4.81MT\;ha^{-1}$. This cultivar is suitable for planting in the plain paddy fields of Honam and Yeonnam regions in Korea.