• Journal of Biosystems Engineering
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• v.12 no.1
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• pp.20-30
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• 1987

Major rice grain losses both in quality and in quantity are incurred in the whitening process which is indispensable in the milling process. Rice whitening it performed by two different whitening actions known as abrasive and frictional. In Korea, abrasive-type whiteners equipped with a emery-stone roller have been adopted in the whitening system in large scale milling plants, but not in customary small scale. However, researches on this type whitener have rarely been conducted in Korea. This study was attempted to establish design criteria or a modified abrasive-type whitener which is aerated with blower. The factors considered in this study were three levels of feedscrew pitch (20, 27, 34 mm) and three levels of clearance(11, 13, 15 mm) between surfaces or emery-stone roller and screen and two levels of moisture content (14.5%, 15.7%, w.b.) of brown rice. Also, the effect of aeration on whitening performance was examined, and a system performance consisting of one pass in the aerated abrasive-type and two passes in the existing friction type was compared with the performance of the existing whitening system consisting of three passes in friction type only. The latter system is prevailed in customery small milling plants. The results of this study are summarized as follows. 1. The interactions between feed-screw pitch and chamber clearance of the aerated abrasive-type whitener had great effect on the performance of the machine. When the value of a nondimensional parameter, $C^2/(P{\cdot}d_p)$, expressing the relations between feed-screw pitch, P, and chamber clearance, C, ranged from 0.40 to 0.45, the performance of the aerated abrasive-type whitener was the best. 2. Aeration to the abrasive-type whitener gave positive effect on milled and head rice recoveries. 3. The whitening system involving the aerated abrasive-type whitener, which has appropriate feed-screw pitch and chamber clearance as described in item 1 above, produced more milled and head rice recoveries by about 1.5% and 2.0%, respectively, than the existing frictional whitening system. The former also consumed less electricity by about 10% (0.9KwH/1000kg).

• Journal of the Korean Society of International Agriculture
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• v.31 no.3
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• pp.249-254
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• 2019

'Japonica 6' is a japonica rice variety developed from a cross between 'MS11', the beginning variety adaptable to tropical region, and 'IR86743-28-1-4', an elite line of high yield and good plant type by a Korea(RDA)-IRRI cooperative breeding program at IRRI in 2017. The growth duration of 'Japonica 6' is 121 days from sowing to harvest. It is 10 days later than that of the check variety 'MS11'. The culm length of 'Japonica 6' is 70 cm, and 1,000-brown rice grain weight is 26.7 g. It has a shorter culm and a larger grain. size than that of MS11. 'Japonica 6' is moderately resistant to blast disease but susceptible to bacterial blight, tungro virus and plant hoppers. The milled rice recovery rate of 'Japonica 6' is improved than that of 'MS11'. The head rice rate of 'Japonica 6' is significantly higher than that of 'MS11'. Yield of 'Japonica 6' is averagely 3.59 MT/ha of milled rice in 5 areas of the Philippines. The 'Japonica 6' was registered in Philippines and would be adaptable to the diverse regions of tropical Asia (Registration No in Philippines. BPI-NSIC-2017-Rc 484SR).

• Food Science and Preservation
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• v.13 no.5
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• pp.543-547
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• 2006

Milled rice was subjected to check the eating quality of rice at various conditions of packaging with haft paper(packaging material made of paper), PE and yellow loess in the ambient conditions($18{\sim}25^{\circ}C$, $18{\sim}34%RH$. Rice packed with yellow loess was shown higher eating quality and less changes in the content of moisture loss and free fatty acid than control(kraft paper, PE). Eventually, yellow loess packaging showed a better performance in the rice storage than kraft paper and PE.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.228-228
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• 2017

Rice production and quality could be changed by temperature condition. Extremely high temperature event have been occurred more frequently for global warming. To increase rice quality against to global warming, breeding of heat tolerance rice cultivar is needed. Ilmi which is the one of Korean leading rice cultivar shows heat stress resistant character during ripening stage. Yield and quality (brown and milled rice) of Ilmi did not show significant different under high temperature condition compared to control condition. However, the main physiological characters for heat resistance of Ilmi have been not investigated yet. Therefore we try to investigate the heat tolerance characters of Ilmi. Two rice cultivars, Ilmi and Ilpum-which is heat susceptible rice cultivar, were cultivated under natural condition in wagnor pot until heading was appeared. After checking heading date, each material was cultivated under different temperature condition, heat($32/22^{\circ}C$) and control($26/16^{\circ}C$) condition. Anti-oxidant enzyme activity was checked during ripening stage in each material. Catalase and ascorbic peroxidase activity of leaf under heat stress condition were higher in Ilmi than Ilpum especially early ripening stage. Analyzing of stress resistance using $H_2O_2$, the flag leaf of Ilmi showed more green color than Ilpum with higher chlorophyll content than those of Ilpum. We also checked the amount of $H_2O_2$ content in young leaf of each material by treating high temperature. $H_2O_2$ content in each material was increased according to treatment time. However $H_2O_2$ content of young leaf in Ilmi was less than those in Ilpum. Also catalase and ascorbic peroxidase activity in leaf increased much faster in Ilmi than Ilpum. With those data, we confirmed that heat stress resistance of Ilmi is due to the higher anti-oxidant activity against to stress condition. We will investigate the heat tolerance characters of Ilmi more in further study to enhance the breeding effect of heat stress tolerance rice.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.366-369
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• 1991

This study was carried out to find out the properties of rice grain with embryo part. Obong-byeo. The embryo part on the rice remained by 96.7% in Obongbyeo after complete removal of the brans by common milling method. In nutritional composition. the content of lipid. vitamin B$_1$ and niacin were greater in Obongbyeo than Nagdongbyeo as a check variety. In particular. the contents of vitamin B$_1$ and niacin were about 1,5 times higher. Increased weight and feed effect of rat raising with milled rice were 107 and 172% in Obongbyeo and 101 and 125% in Nagdongbyeo. respectively. Eating quality of Obongbyeo was better than Nagdongbyeo.

• Applied Biological Chemistry
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• v.44 no.3
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• pp.179-184
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• 2001

To investigate the effects of harvesting times on physicochemical and milling properties of rice, milling tests were performed applying laboratory milling systems. Milling and head rice yields were highest in rice harvested at the 45 days after heading at 76.49 and 94.43%, respectively. Milled rice grain harvested 45 days after heading showed the highest minimum viscosity, as shown in the amylogram curves, as well as the lowest consistency viscosity. Protein and amylose contents were highest in rice harvested at 35 days after heading, whereas the instrumental taste score was highest 45 days after heading.

• Microbiology and Biotechnology Letters
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• v.7 no.1
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• pp.15-21
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• 1979

In order to find out a reliable chemical indicator which can be used to tell whether rice, during storage, is invaded by fungi or not, 90 percent milled rice (Tongil) was stored at 26$^{\circ}C$ for 4 weeks and weekly analyzed for changes in several chemical components. The results were as follows : 1) Of several genera of fungi (Aspergillus sp., Penicillium sp., and Rhizopus sp.) observed in stored rice after surface disinfection, Aspergillus sp. were the most frequent fungi. 2) Chitin content in the rice was 25 ug/g at the beginning of the experiment and increased proportionly with moisture content of the storedrice to become 1980 ug/g at 26.9％ moisture after 4 weeks. 3) Non-reducing sugartended to decrease with increasing moisture content and or prolonged period. 4) Fat acidity showed a tendency of increase with rise in moisture content of the stared rice. Consequently, changes in chitin content can be mployed as a reliable measure to evaluate the quality of stored rice in connection with fungal invasion.

• 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.

• 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 $4^{\circ}C$