• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1407-1414
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• 2014

Physicochemical properties of rice-based expanded snacks extruded with rice flour, high amylose starch, and isolated soy protein were investigated using a twin-screw extruder. The ingredients were extruded at various feed moisture contents (19~23%) and screw speeds (200~400 rpm) at a constant feed rate (43.4 kg/hr). Bulk density and apparent density of rice snacks were 0.06~0.21, and 0.55~0.65 respectively. Bulk density, apparent density, water absorption index, and breaking strength of rice snacks increased with increasing feed moisture content and decreasing screw speed. However, expansion and water solubility index of rice snacks increased with decreasing feed moisture content and increasing screw speed. Hunter's color L values of rice snacks was lower with increasing screw speed at feed moisture contents of 19% and 21%, but was not significantly different from a feed moisture content of 23%. On the other hand, a and b values of rice snacks were higher with increasing screw speed a feed moisture content of 19%. X-ray diffraction intensity of rice snacks decreased with decreasing feed moisture content and increasing screw speed. X-ray diffraction of rice snacks was V-type at feed moisture contents of 19% and 21% and screw speeds of 300, and 400 rpm. In the microstructure of the cross section of rice snacks, air cells in rice snacks were not well formed, and cell walls were thicker with increasing feed moisture content and decreasing screw speed.

• Korean Journal of Organic Agriculture
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• v.24 no.2
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• pp.221-234
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• 2016

The application of animal manure on farm fields is one of the most economical ways. However, the continuous application of manure in paddy fields might change soil properties influencing the growth of rice plant. Thus, this study was conducted to investigate the changes in selected chemical and biological properties of soils and rice production as affected by the applications of two different fertilizer sources, which were the consecutive applications of liquid swine manure (LSM) and chemical fertilizer (CF), during the three experimental years, from 2012 to 2014. Application amount of LSM was based on 100% of nitrogen fertilizer recommendation rate for rice cultivation estimated by soil testing. Plant height and tiller number in rice at the first year of liquid swine manure manure plot were lower than those of chemical fertilizer plot. Height and tillers of rice in liquid swine manure plot were higher than those of rice in chemical fertilizer plot after consecutive application for 3 years. Rice yield In the first year of application was decreased by 7% than that of chemical fertilizer, but the yield of rice in the third year of application in LM 100% plot was increased by 8% compared to the chemical fertilizer. Toyo-taste value of milled rice in LM 100% was decreased by increasing of protein contents and decreasing rate of perfect grain. The K and Zn contents in the soil were increased in the plots of consecutive LSM application. The results implied that the liquid manure may neither decrease the yield of rice and nor increase soil properties except K and Zn in the soil, and decrease rice quality.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.6
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• pp.892-897
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• 2006

An experiment was designed to study the nutritional value of Chinese brown rice and maize for growing pigs. Six male grower pigs (Duroc${\times}$Landrace${\times}$Large White, $24.3{\pm}1.26$ kg average initial BW) were surgically fitted with a simple T-cannula at the terminal ileum and allotted within a $2{\times}2$ Latin square design. The pigs were fed either a maize or brown rice diet in a direct method to determine their digestibility. The brown rice used in this experiment was husked from one kind of early, long grain, and non-glutinous rice (ELGNR, indica rice: non-waxy rice, containing amylopectin and amylose) in southern China. Chromic oxide was used as a marker. The diets were supplied at about 4.0% of body weight in dry matter/d. Total faeces and urine were collected on days 4 and 5; digesta was collected on days 6-8 in each period. The average body weight was 24.3 kg at the start of the experiment and 27.6 kg at the end. The results showed that the apparent ileal digestibilities of most amino acids of brown rice were significantly higher than those in maize (p<0.01), as were the apparent ileal digestibilities of crude protein (CP), digestible energy (DE), organic matter (OM) and dry matter (DM) (p<0.05). However, the apparent ileal starch digestibilities of the two treatments were similar (p>0.05). The values of the apparent faecal digestibilities derived from the two methods, marker and total faecal-collection methods, were very similar and also correlated with each other. The difference in absolute value of the apparent faecal digestibilities between brown rice and maize was smaller compared to that of the apparent ileal digestibilities. The net protein utilization was higher (p = 0.07) and the DE metabolizable rate was significantly higher (p<0.01) for brown rice than for maize. The metabolizable energy (ME) of brown rice is similar to that of maize, while the DE of brown rice was relatively lower. It can be concluded that Chinese brown rice are better than maize not only in apparent ileal digestibilities, but also in metabolizable rate of amino acids and gross energy under the present study conditions.

• Food Science and Preservation
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• v.8 no.2
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• pp.140-145
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• 2001

Although the drying times of paddies were significantly shortened by the application of higher drying temperatures, the 12, 10 and 8 hours were needed for the reduction of moisture contents from 23.55 to 15% at the temperatures of 45, 50 and 55$\^{C}$, respectively. Milling yields(MY) and rice rates(HRR) were decreased by increasing of the drying temperature. The MY ratios were 75.50, 75.42 and 75.31% and HRR were 93.28, 92.14 and 91.12% in drying temperature of 40, 50 and 55$\^{C}$, respectively. In the milling processes of tough rice with the used of a milling machine equipped with both of abrasive and friction types in a body, the reduction rates of bran and the occurrence of broken rice increased with the pressures at outlet or the recycled passing tines. In the process for humidified friction whitening of rice, it was found that the optimum addition rate of water for the best quality was the 11.2 liters per tone of white rice.

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.93-98
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• 1999

We had investigated combustion properties of rice bran dusts. Decomposition of rice bran dusts with temperature were investigated using DSC and the weight loss according to temperature using TGA in order to find the thermal hazard of rice bran dusts, and the properties of dust explosion in variation of their dust with the same particle size. Using Hartman's dust explosion apparatus which estimate dust explosion by electric ignition after making dust disperse by compressed air, dust explosion experiments have been conducted by varying concentration and size of rice bran dust.According to the results for thermodynamic stability of rice bran dust, there are little change of initiation temperature of heat generation and heating value for used particle size. But initiation temperature of heat generation decreased with high heating rate whereas decomposition heat increased with particle size. Average maximum explosion pressure was $10kgf/cm^2$ for 60/70 mesh and $1.5mg/cm^2$ dust concentration.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.863-877
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• 1996

A drying model to predict the drying process in continuous dryer was developed and proved by drying experiments. The experiment showed that the difference of moisture contents between the predicted and the observed was within 0.5%(wb). There was no cracked rice found even in high drying rate with the inlet moisture content over 23%(wb), and tempering treatment in the same temperature reduced the ratio of cracked rice. There was a little difference in the ratio of cracked rice between 40$^{\circ}C$ and 45$^{\circ}C$ drying temperatures with the final drying moisture content (14.5% wb), and the cracked rice increased at 55$^{\circ}C$. As a results, it was better to make fast drying on the rice over 23%(wb) inlet content it was recommended to keep drying at 45$^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.1
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• pp.1-6
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• 1989

Nutritive values and fermentation rates of rice straw treated with 3% anhydrous and 3% aqueous ammonia were evaluated both in vitro and sheep metabolism trials. Daily gain, feed efficiency and feed cost per gain were also determined with growing Holstein bulls fed anhydrous and aqueous ammonia treated rice straw. Crude protein was increased 2.4 fold and NDF was decreased 6.5%, but ADF and cellulose were not different between untreated and ammonia treated rice straw. An average of 35.5% of total added ammonia-N retained in the rice straw and other 64.5% was not retained in the rice straw. Ammonia treatment increased in vitro DM, NDF, ADF and cellulose digestibilities by 44.8%, 43.3%, 49.4% and 42.4%, respectively, and fermentation rates by 63.3%, 132.4%, 49.4% and 42.4%, respectively. In sheep metabolism trials, DM digestibilities of rice straw treated with anhydrous and aqueous ammonia were increased 22% and 36%, respectively, and digestible DM intakes by 48% and 70%, respectively in sheep fed anhydrous and aqueous ammonia treated rice straw over untreated rice straw. Rumen ammonia and blood urea were considerably higher in sheep fed ammonia treated rice straw than sheep fed untreated rice straw. Daily gain of Holstein bulls was increased 20.8% and 29.9% and rice straw intakes were increased 28.4% and 44.3% in anhydrous and aqueous ammonia treated rice straw over untreated rice straw. Feed conversion was improved 9.5% and 10.3% and feed cost/gain was reduced 7.1% and 9.2% respectively in anhydrous and aqueous ammonia treated rice straw group as compared with untreated rice straw group.

• Journal of Biosystems Engineering
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• v.32 no.1 s.120
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• pp.13-19
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• 2007

Storage rough rice in low temperature using the winter cold air avoids rough rice temperature increase which happens from early May, and this is possible by installing a cooling system in the top of a bin, the room between top rice level and bin ceiling. The research objective is to establish low temperature rough rice storage technique, furnishing winter cold air to rough rice, by investigating the cooling system potential of maintaining low rough rice temperature and by analyzing rough rice storage characteristics over a storage period. The rough rice storage characteristics were evaluated from January to August 2003, using a storage and dry bin of 400-ton capacity. Results of this research are as follows: Cooling bin using the cooling system in the top of the bin maintained the rice temperature less than 15$^{\circ}C$ in entire portions in August. Moisture contents and germination rates of rough rice were decreased over the storage period, on the other hand, the rough rice stored in the ambient temperature bin had relatively lower moisture contents and germination rates to compare with the bin using winter cold air. Crack ratio and acid value of brown rice in the ambient temperature bin storage had increased more than the cooling bin storage. The result indicates that the storage bin using winter cold air and the cooling system maintains moisture content and germination of rice, minimizes cracked kernel and acid value, and preserves rice quality as well.

• Korean Journal of Agricultural Science
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• v.31 no.2
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• pp.135-148
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• 2004

Rice is not only main food but also key farm income source of Korean farmers. In spite of the above facts, rice productivity was decreased on account of drought in every 2 or 3 years interval owing to the vulnerability of irrigation facilities throughout Korea in the past decades. As an context of the first five year economic development plan, all weather farming programme including 4 big river basin comprehensive development projects and large and medium sized irrigation water development projects were carried out successfully. Therefore the area of irrigated paddy were increased from 58% in 1970 to 76.2% in 1999. In the past decades, the Government had invested heavy financial funds to develop irrigation water but as an factor share analysis, the contribution rates of irrigation water and investment for farmland base development project have not been identified yet in national agricultural economic level. It is very scarce to find out the papers concerned to macro-economic factor share analysis or contribution rates of water and investment cost to rice production value in Korea considering the production function of the quantity of irrigation water and investment cost as independent variables. Accordingly this paper covered and aimed at identifying (1) derivation of rice production function with the time serial data from 1965 to 1999 and the contribution rates of irrigation water and total investment cost for farmland base development project. The analytical model of the contribution rates was adapted the famous Cobb-Douglass production function. According to the model analysis, the contribution rate of irrigation water to rice production in Korea was shown 37.8% which was equivalent to 0.28 of the production elasticity of water. The contribution rate of farmland base development project cost was revealed 22% and direct production cost of rice was contributed 60% in the growth of rice production and farm mechanization costs contributed to 18% of it respectively. The two contribution rates comparing with the direct production cost were small but without irrigation water and farmland base development, application of high-pay off inputs and farm mechanization might be impossible. Considering the food security and to cope with the frequent drought, rice farming and investment for the irrigation water development should be continued even in WTO system.

• Applied Biological Chemistry
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• v.36 no.3
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• pp.146-153
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• 1993

The changes in water uptake rate, cooking property, color of rice grain, gelatinization property of milled rice during storage were studied. The water uptake rate constant of milled rice during storage at $4{\sim}30^{\circ}C$ for 3 months decreased, which was more pronounced at elevated storage temperatures. The activation energy of water uptake was different below and above $25^{\circ}C$ of storage temperature. The activation energy after storage for 3 months below and above $25^{\circ}C$ was 608 and 1269 cal/mole, respectively. The rice grain became harder and the cooking time was prolonged by $3{\sim}8$ minutes upon storage. The cooking rate constant was linearly decreased as a function of storage time. The activation energy of cooking after 1 month of storage was 235 cal/mole, which was increased by 1.7 times after storage of 1.5 months and thereafter by 1.2 times with the increase of 0.5 month. There were no significant changes in color of milled rice grains during storage at $4^{\circ}C$, but the increase of b value was observed at higher temperatures. The Initial pasting temperature of rice flour remained essentially unchanged during storage, but the peak viscosity consistently increased with the increase of storage time and temperature. The gelatinization temperature of rice flour by differential scanning calorimetry was not changed but enthalpy of gelatinization was decreased during storage.