• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.569-575
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• 1982

Mechanical properties of rice plants were tested to determine compressive force, bending force, tensile force and shear force for improvement of harvesting machines and for efficient utilization of rice culm during the proper harvesting period. Rice varieties used in this study were two Japonica varieties with Irri 348 and Jinju, and two $Indica{\times}Japonica$ hybrids with Seogwang and Taebaeg, which were grown in the standard fertilization field of Chungnam Rural Development Office. Also Jinju and Taebaeg were tested to elucidate the shearing characteristics which included shear force-strain relationship, shear force and shear energy according to the position from the ground level, the shearing angle to the rice culm, and the moisture content. 1. Compressive force, bending force, tensile force and shear force were higher In Japonica varieties than $Indica{\times}Japonica$ hybrids. 2. Shear force to overall culm length decreased progressively to upper positions in Jinju variety but a constant shear force was approximately showed between the ground level and the position of 21cm in Taebaeg variety. 3. Shear force and shear energy increased with increase of the cross sectional area, and the rates of increase were high in general up to the cross sectional area of $10mm^2$ and then they became dull very much. 4. Shear force and shear energy decreased with decrease of moisture content of rice culm after cutting up to the moisture content of 60% (w. b.) and then they did not change significantly.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.447-451
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• 2008

'Goamibyeo', a mid-late maturing ecotype with high amylose content in kernels, was developed by the rice breeding team of National Yeongnam Agricultural Experiment Station(NYAES) in 2000 and released in 2001. This variety was derived from the three way cross of Milyang 95//Kimcheonaengmi/$2^*Ilpumbyeo$ (in 1992 summer) through the pedigree breeding method and designated as 'Milyang 168' in 1997. The heading date of 'Goamibyeo' was Aug. 18 in ordinary season with culm length of 85 cm. However, 'Goamibyeo' showed susceptible to bacterial leaf blight, stripe virus and leaf blast disease. The amylose content of 'Goamibyeo' in milled rice kernels is about 26.7% with translucent and clear in chalkness. Thus, 'Goamibyeo' is expected to be used as a source grain for rice noodle industries. The milled rice yield potential of 'Goamibyeo' is about 5.38 MT/ha in local adaptability test of three years and it would be adaptable to Yeongnam plain of Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1173-1178
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• 2012

Water competition among domestic, industrial and agricultural sectors has been gradually heightened recently in Korea as the lack of water supply is expected in the near future. About 46% of nation's water use is consumed in paddy farming to produce rice. And the conservation of water resource and quality in agricultural sector is a pending issue in the nation's long term water management plan. New paddy rice farming techniques that use significantly less irrigation water are urgently required. System of Rice Intensification (SRI) that is now well known to produce more rice with less water consumption has not been tried in Korea yet. And environmental effect of SRI on greenhouse gases (GHGs) has not been well investigated. The objective of this study was to measure the effect of SRI on GHGs as well as water use and rice yield in a Korean paddy condition. Three experimental runoff plots $5{\times}15m$ in size were prepared at an existing paddy field. Runoff, GHGs emission and water quality were measured during the 2011 growing seasons while a Japonica rice variety was cultivated. Rice plants grew better and healthier in SRI plots than in continuously flooded (CF) and intermittently drained (ID) plots. Rice yield from SRI plots increased 112.8 (ID)~116.1 (CF)% compared with CF and ID plots. Irrigation requirement of SRI plots compared to CF plot reduced by 52.6% and ID plot reduced by 62.0%, meaning that about 37.9~47.4% of irrigation water could be saved. GHGs emission from SRI plots reduced by 71.8% compared to that from CF plot and by 18.4% compared to that from ID plot, meaning that SRI could help contribute to ease the greenhouse gas accumulation in the atmosphere. It was believed that SRI is a promising paddy farming technique that could increase rice yield, and reduce irrigation water requirement and GHGs emission not just in Korea but also other rice farming countries all over the world. However, it was recommended that long term studies under different conditions including rice variety, soil texture, water source, climate need to be conducted for reliable data for the development of environmental policies related to GHGs emission control and management.

• Korean Journal of Agricultural Science
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• v.16 no.1
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• pp.1-18
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• 1989

This experiment was undertaken to clarify derivation of resistance of Japonica type of rice varieties to rice blast in Korea and to classify Japonica type of rice varieties on the basis of their rice blast reaction in the blast nuisery test. 1. The resistance of Iljin, Kwancheok 9, Koshi, Baedal and Paldal, Jaekeon, Sinpung, Jinheung, Hokwang and Palkeum, and Gwangmyungbyeo and Yeongdeogbyeo to rice blast was derived from Kyudai Taicho Asahi 3, Futaba and 2067, respectively. 2. The resistance of Kwanok, Mankyeong and Nongbaek to the rice blast was derived from Kanto 55, Hokwang and Kusabue, and Ishigarisiroge, respectively. 3. The resistance of Seomjinbyeo, Sinseonchalbyeo, Donghaebyeo and Tamjinbyeo to the rice blast was derived from Milyang 20 and the source of resistance to the rice blast in Jinjubyeo and Daecheongbyeo was HR 769 or HR 1590. 4. The resistance of Dobongbyeo, Gwanagbyeo and Chiagbyeo to the rice blast was derived from Tjina, Kongo and Kuik 90, respectively. 5. The resistance of Seolagbyeo, Seonambyeo, Kihobyeo, Namyangbyeo, Samnambyeo, Seohaebyeo, Whaseongbyeo, Daegwanbyeo and Taeseongbyeo, and Sobaegbyeo, Odaebyeo and Unbongbyeo to the rice blast was derived from Fuji 280 and Fuji 269, respectively. 6. The source of resistance to the rice blast in Cheonmabyeo and Baegambyeo was BL 7 and Nongbaek, the resistance of Dongjinbyeo and Sangpungbyeo to the rice blast was derived from Satominori and Simokita, respectively. 7. Japonica type of rice varieties was classified into eleven varietal groups according to their reaction to the blast as follows. Eight varieties of Jinheung group, two varieties of Dongjinbyeo group, two varieties of Jinjubyeo group, three varieties of Gwanagbyeo group, four varieties of Sobaegbyeo group, one variety of Nongbaek group, two varieties of Baegambyeo group, five varieties of Sinseonchalbyeo group, five varieties of Seonambyeo group, two varieties of Taeseongbyeo group and some variety of Nagdongbyeo group.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.39-74
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• 2001

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s∼1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great, progress and success was obtained in development of high-quality japonica cultivars and qualify evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice caltivars and special rices adaptable for food processing such as large kernel, chalky endosperm aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic mcroscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high Probability of determination. The ${\alpha}$ -amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice bread. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

• Korean journal of food and cookery science
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• v.29 no.2
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• pp.95-104
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• 2013

This study was conducted to investigate the current use and the demand for processed rice food products by full-time and working housewives in a metropolitan area. Out of 330 questionnaires distributed, 300 were analyzed(90.9% response rate). It was revealed that more than half of the respondents(54.0%) had used processed rice food products, regardless of their occupation. Most respondents stated that they used rice food products because of the variety of the products, digestibility and the taste. The development necessity for processed rice food products was analyzed, showing that rice cake(3.86), rice sauce(3.64), and rice cookie(3.89) had the highest score in each category. The average demand for education and promotion of rice food products was 3.89; among 7 items, menu recipe using rice flour was highly demanded(4.18) by the respondents. Approximately 43.0% of the respondents agreed that the internet is the most effective method for learning about rice flour cooking, and the respondents who have used processed rice food products(59.5%) were more likely to attend education programs compared to housewives who have not used processed rice food products (44.5%)(p<.05). Full-time housewife(59.4%) had a greater tendency to participate in the education program than working woman(44.4%)(p<.001). The findings suggested that various processed rice flour products with convenience to use and prolonged shelf-life will be needed.

• Preventive Nutrition and Food Science
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• v.13 no.4
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• pp.276-280
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• 2008

Oryza sativa cv. Heugjinjubyeo, an anthocyanin-pigmented rice variety, is well known to contain high levels of bioactive phytochemicals, anthocyanin, quinolone alkaloids and phenolic acids. Here, we studied the inhibitory effect of Oryza sativa cv. Heugjinjubyeo bran on the absorption of dietary fat in streptozotocin-induced diabetic Sprague-Dawley male rats. For these experiments, experimental animals were divided into four groups: normal, diabetic-control and two experimental groups that were fed 1.0 g or 2.0 g/kg body weight/day of Oryza sativa cv. Heugjinjubyeo bran supplement for 14 days. As a result, liver glycogen levels increased significantly by 65% and 32% in groups receiving 1.0 g and 2.0 g/kg body weight/day, respectively, compared to diabetic-control. Liver cholesterol levels were significantly lower by 8.3% and 14.5% in the groups fed 1.0 g and 2.0 g of anthocyanin- pigmented rice extracts, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.12
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• pp.5047-5056
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• 2016

Colorectal cancer (CRC) is a major worldwide health problem owing to its high prevalence and mortality rates. Carcinogenesis in the colon is a multistage and multifactorial process. An imbalance between free radical exposure and anti-oxidant defense systems may leads to oxidative stress and attack of macromolecules which can alter signal transduction pathways and gene expression. Consequently, oxidative damage can lead to cellular dysfunction and contribute to pathophysiological processes in a variety of diseases including CRC. One factor tightly associated with CRC is chronic inflammation, which can be present from the earliest stage of tumor onset. Unpolished rice is an attractive chemoprevention in CRC due to their anti-oxidant and anti-inflammatory activities. The aim of this paper is to review evidence linking oxidative stress and inflammation to CRC and to provide essential background information for understanding future research on oxidative stress and inflammation on CRC. Mechanisms of action of unpolished rice in CRC carcinogenesis are also discussed.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.282-290
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• 2008

The malting process of rice (OM4080 variety from Mekong Delta Rice Research Institute) was studied under pilot condition plan by means of the second-order experimental design. Processing parameters, such as the steeping time (0-60 hrs), steeping temperature ($5-45^{\circ}C$), germination time (0-8 days), germination temperature ($5-45^{\circ}C$) and gibberellin concentration (0-2 mg/kg) were investigated. As a result, all germination conditions, especially germination time, germination temperature, and gibberellin concentration had a significant effect on the malting loss, amylase activity and starch content. The protein content was not clearly affected by any conditions. The optimum conditions for malting process (with highest amylase activity) were as follows: 30 hrs of steeping time, $30-35^{\circ}C$ of steeping temperature, 5-5.5 days of germination time, $25^{\circ}C$ of germination temperature, and 1.5 mg/kg of giberrellin concentration.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1439-1446
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• 2009

The surfaces of different-sized endosperm, bran, and husk rice powders were modified using carboxymethylation. Carboxymethylation was carried out using aqueous alkalization and neutralization. After the carboxymethylation process, the centrifuged products were milled and classified by size: particles passed through sieves of 45, 106, and $300-{\mu}m$ width. The effect of carboxymethylation on physical properties such as solubility and dispersibility of endosperm, bran, and husk particles were studied. Overall, carboxymethylation increased solubility of the particles, while size reduction increased dispersibility. In particular, carboxymethylation created good aqueous suspensions by minimizing interparticle agglomeration. Our results show that the combination of size reduction and carboxymethylation improves solubility and dispersibility, resulting in better stability of the suspension. This study may be helpful for expanding the use of rice and its byproducts as ingredients in a variety of food and beverage applications.