• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.635-643
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• 2017

The properties of rice were studied, and 8 rice flour cultivars were used to study the effect of particle size on the physicochemical properties, color value, RVA viscosities, water absorption index (WAI), and water solubility index (WSI) of rice flours. The mean particle size by the 3 particle size classification of 150 mesh, 200 mesh, and 250 mesh was, $90.75{\mu}m$, $60.73{\mu}m$, $39.94{\mu}m$, respectively. Thai rice had the highest amylose content and Samkwang rice had the lowest amylose content. Protein content of rice flours prepared was decreased as the particle size of rice flour decreased. In terms of color values, the L-value and the a-value of rice flour were increased as the particle size of rice flours decreased, while the b-value was decreased as the particle size of rice flours decreased. Using a rapid visco analyzer (RVA), the initial pasting temperature of Thai rice cultivar was found to be the highest; the peak viscosities of Sunpum cultivar and Misomi cultivar, and Samkwang rice were higher than those of other rice flours. The water absorption index and water solubility index were increased as the particle size of rice flour decreased. In order to use processed rice flour for the development of processed foods, proper characteristics of the cultivars and particle size should be considered.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.10-10
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• 2017

Rice consumption has been continuously decreasing as the eating habits of Koreans have become westernized and diversified. The per capita annual rice consumption in Korea has dropped sharply from 136.4 kg in 1970 to 61.9 kg in 2016. The Korean government, therefore, has been trying to promote rice consumption by invigorating the processed food industry using rice flour. To facilitate the market for processed rice foods, it is essential to develop proper milling technology in terms of flour particle size and damaged starch content to produce high quality rice flour at competitive cost. Dry milling and wet milling are the two major processes used to produce rice flour. Although the dry milling process is relatively simple with a lower production cost, damaged starch content increases because of the high grain hardness of rice. In wet milling, the quality of rice flour is improved by reducing flour particle size as well as damaged starch content through soaking procedures. However, the production costs are high because of the additional expenses associated with the disposal of waste water, sterilization and drying of the wet flour. Recently developed technologies such as jet milling and cryogenic milling also require expensive investment and production. Therefore, developing new rice cultivars with dry milling adaptability as well as good processing properties is an important goal of rice breeding in Korea. 'Suweon 542' is a floury endosperm mutant line derived from sodium azide treatment on a high-yield, early maturing, and non-glutinous japonica rice cultivar, 'Namil'. Compared with the wild type, after dry milling process, the grain hardness of 'Suweon 542' was significantly lower because of its round and loosely packed starch granules. Also, the flour of 'Suweon 542' had significantly smaller particles and less damaged starch than 'Namil' and other rice cultivars and its particle size distribution was similar to a commercial wheat cultivar. Recently, through collaborations with nine universities and food companies, a total of 21 kinds of processed prototypes, using the dry milling flour of 'Suweon 542', were evaluated. In the production of major rice processing products, there was no significant quality difference between the flours prepared by wet milling and dry milling. Although the amount of water added to the dough was slightly increased, it was confirmed that the recipe applying the wet flour could be used without significant change. To efficiently transfer the floury endosperm characteristics of 'Suweon 542' to other commercial rice cultivars, it is essential to develop DNA marker tightly linked to the target gene. Association analysis using 70 genome-wide SSR markers and 94 F2 plants derived from 'Suweon 542'/'Milyang 23' showed that markers on chromosome 5 explained a large portion of the variation in floury grains percentage (FGP). Further analysis with an increased number of SSR markers revealed that the floury endosperm of 'Suweon 542' was directed by a major recessive locus, flo7(t), located in the 19.33-19.86 Mbp region of chromosome 5, with RM18639 explaining 92.2% of FGP variation in the F2 population. Through further physical mapping, a co-segregate and co-dominant DNA marker with the locus, flo7(t) was successfully developed, by which, thereby, breeding efficiency of rice cultivars having proper dry milling adaptability with high yield potential or useful functional materials would be improved. 'Suweon 542' maintained the early maturity of the wild type, Namil, which can be used in rice-wheat double cropping systems in Korea not only for improved arable land but also for sharing flour production facilities. In addition to the high susceptibility against major rice diseases, nevertheless, another possible drawback of 'Suweon 542' is the high rate of viviparous under prolonged rainfall during the harvesting season. To overcome susceptibility and vivipary of 'Suweon 542', the progeny lines, derived from the crosses 'Suweon 542' and 'Jopyeong', an early maturing rice cultivar with multiple resistance against rice blast, bacterial blight, and rice strip virus, and 'Heugjinju', a anthocyanin pigment containing black rice cultivar, were intensively evaluated. As the outputs, three dry milling suitable rice elite lines, 'Jeonju614', 'Jeonju615', and 'Jeonju616' were developed.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.289-297
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• 2006

In this study we examined the changes in weight and dimension, protein and amylose contents, and pasting properties of brown rice flour, as well as the gelatinization properties of starch, from two non-waxy japonica cultivars and one waxy japonica cultivar planted in an experimental field in 2002 under the same fertilizer conditions. The weight of both rough and brown rice increased consistently up to 42 days after flowering (DAF) for the non-waxy rice and to 35 DAF for the waxy rice. The changes in dimension of the brown rice kernel indicated that the length was maximized first, followed by breadth and then thickness. The protein content of the non-waxy rice remained fairly constant, but that of the waxy rice decreased by about 1% after 14 DAF. The amylose content of the non-waxy brown rice flour increased, but that of the waxy brown rice flour decreased during kernel development. As the kernel developed, the peak viscosity of the non-waxy rice flour increased up to 35 DAF, after which it decreased, whereas that of the waxy brown rice flour increased consistently. The gelatinization temperature of starch also increased in the waxy rice during kernel development up to 21 DAF. The gelatinization enthalpy of starch, however, increased in all rice cultivars throughout the kernel development.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.286-286
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• 2017

We conducted to compare the characteristics of rice flours according to the different milling processes. Five rice varieties (Oryza sativa L.) with different amylose content were prepared by wet and dry milling processes. The moisture contents of wet-milled rice flours (WMR) was mostly three-time higher than those of dry-milled flours (DMR). Water absorption index (WAI), water solubility index (WSI) and swelling power (SP) increased in proportion to temperature ($50-90^{\circ}C$). WAI, WSI, SP of DMR showed higher value than those of WMR. Baeokchal (BOC) which is waxy rice cultivar was significantly high level of WSI. Pasting properties of DMR except BOC cultivar resulted in higher peak viscosity, trough viscosity, final viscosity and Setback. The levels of resistant starch in the four cultivars except Dodamssal (DDS) were under 1% irrespective of Milling processes, whereas the resistant starch contents of DMR and WMR in DDS was 9.18 and 6.27, respectively. Damaged starch content of WMR were less than those of DMR, moreover, negative correlation was observed between amylose content and damaged starch of rice cultivars. These results suggest that the properties of rice flour varied depending on the milling methods and varieties, and it could be a reference for selecting the appropriate processing purposes.

• Korean journal of food and cookery science
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• v.28 no.5
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• pp.541-547
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• 2012

This study was performed to compare the processing aptitudes of the rice muffins produced from the seven rice varieties, including Goami, Goami 2, Deuraechan, Baegjinju, Seolgaeng, Haiami and Hanareum, along with the use of hydroxypropyl methylcelluloses (HPMCs) as a replacement for the egg white. The water binding capacity of rice flours was significantly higher than that of wheat flour, but its fat binding capacity was lower than that of wheat flour (p<0.05). In the viscosity of the batter, Goami and Baegjinju were lower than that of the wheat flour. There was no significant difference in the specific gravity of Seolgaeng and the batter of wheat flour. The pH of all varieties except Goami 2 was higher than batter of wheat flour(p<0.05). Haiami flour produced higher muffin volume and specific volume compared with the wheat flour muffin. The textural characteristics, the muffins produced by Haiami and Hanareum flours had significantly lower hardness than the wheat flour muffin after 30 hours. All rice varieties except Gaomi 2 showed no significant difference compared to the wheat flour muffin in color, taste and texture (p<0.05). Furthermore, flavor of muffins produced from the Seolgaeng, Haiami and Hanareum flours tested higher than the wheat flour muffin. It was concluded that the rice varieties of Seolgaeng, Goami, Haiami and Hanareum were considered to be the most suitable rice cultivars for the rice muffins.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.331-331
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• 2017

This study was conducted to know the influence of air temperature and sunshine duration on yield, chemical component, pigment color difference and starch characteristics of two colored rice cultivars in the plain area of Yeongnam province in Korea. The $L^*$, $a^*$, and $b^*$ value of brown rice in Hongjinju and Josaengheugchal rice cultivars was significantly different at continuous cultivated years, 2015 and 2016. The $L^*$, $b^*$ value of two colored rice was significantly increased in 2016 compared to 2015. The $a^*$ value of Josengheugchal rice cultivar was also significantly higher at 2016 than at 2015. It can be noticed the $a^*$, $b^*$, $L^*$ values in Josaengheugchal varied more than those in Hongjinju. Air temperature during ripening period in 2016 was higher than 2015, especially minimum temperature was too high to proper maturation for rice quality. In Josaengheugchal rice cultivar, sunshine duration after heading was longer in 2016 than in 2015. On the contrary, Hongjinju rice cultivar was ripened under condition of insufficient sunshine duration in 2016. The short growing duration by high temperature and long shiny duration made the lack of pigment for Josaengheugchal brown rice. In Hongjinju rice cultivar, shorten sunshine duration and higher night temperature were the source of the pigment deficiency. The grain size of rice which produced in 2016 was bigger than that of 2015 in both rice cultivars. The 1,000 grain weight of rice from 2016 was also bigger than that of 2015. Head rice ratio was high in the rice cultivars produced in 2015. Protein of milled rice in 2016 was more decreased than that of 2015 in Josaengheugchal rice cultivar, it showed reverse result in Hongjinju rice cultivar. Amylose contents of milled rice in 2016 were more decreased than that of 2015 in Hongjinju rice cultivar. Branch chain length distribution of amylopectin was shown a distinct difference between Josaengheugchal and Hongjinju rice flours by each produced year. Josaengheugchal rice cultivar produced in 2015 had a higher amount of short chains than that of 2016 rice starches. In Josaengheugchal rice cultivar, the pasting temperature and peak, trough, breakdown, final viscosity increased in rice flour which produced at 2016, whereas the setback viscosity and peak time showed lower value than those of rice from 2015. The most pasting properties (except of setback viscosity) of rice starch in Hongjinju rice cultivar grown in 2015 were higher than those of rice cultivar produced in 2016.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.276-276
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• 2017

This study was examined to establish a conditions for producing Tteokbokki using dry-milling rice flour which can save manpower and labor time. Since the cost of producing rice flour milled in a wet condition is 500 to 700 won/kg, which is more than twice as much as that of 300 won wheat flour, it is necessary to directly make rice flour from raw rice. The dry-milling rice flour used in the experiment was produced by Air mill (Nara machinary co. ltd., Tokyo, Japan) from 5 rice cultivars (Samkwang, Dasan-1, Boramchan, Seolgaeng, Hanareum-2), which were cultivated in A-san in 2015 year. Their particle sizes were 50, 100 and $150{\mu}m$ for each cultivar, respectively. A control was a wet-milled rice flour milled with a roll mill after the rice was soaked in water for 4 hours. The moisture content of dry-milling rice flour based on cultivars was 11 ~ 12%, and added water up to 50~55% of dry-milling rice flour weight. The RVA characteristic of peak viscosity was the highest in Dasan-1 and Hanareum-2, the lowest in Seolgaeng. The setback value used as an indicator of aging was the highest in Dasan-1, therefore Dasan-1 was expected to be quick solidification, resulting in the low tendency of sensory evaluation. The damaged starch was high in Dasan-1 and Boramchan (p<0.05) compared to others. The Hunter color L were no significant among cultivars and b value increased in all cultivars of dry-milling rice flour compared with control. The hardness of dry-milling rice flour was higher than that of the control, especially Dasan-1 and Hanareum-2 were the highest. Based on the sensory evaluation, the best cultivars were Boramchan, Hanareum-2 and Samkwang. The overall preference of dry-milling rice flour was good in particle size of 50~100um.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.618-627
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• 2016

This study evaluated the hydration, gelatinization, and saccharification properties of rice processing for beverage development. The properties of rice were studied on 10 rice cultivars (Samkwang, Ilpum, Seolgaeng, Anda, Dasan-1, Goami-4, Danmi, American rice, Chinese rice, and Thai rice) and employing four kinds of pre-treatment methods (dry grain, wet grain, dry flour, and wet flour). The results showed that moisture content of rice was between 11.88~15.26%. Increase in soaking time along with highest water absorption was noted in American rice cultivar (46.81%). The water binding capacity of Thai rice was higher when compared to that of other rice flours. In addition, solubility and swelling power of rice were 4.52~26.65% and 0.19~2.05%, respectively. The amylose content of Goami-4 was higher in rice processing. Using a rapid visco analyzer (RVA), the initial pasting temperature of Danmi cultivar was found to be the highest; the peak viscosities of Anda cultivar and Dasan-1 cultivar, and Chinese rice were higher than of those of other rice flours. After saccharification, the pH, soluble solids content, and reducing sugar content of rice processed through different pre-treatment methods were in the range of 6.22~7.08, $4.67{\sim}16.07^{\circ}Brix$, and 0.35~11.67% (w/w), respectively. In terms of color values, the L-value of dry grain, a-value of wet (grain, flour), and b-value of dry sample (grain, flour) were found to be the highest. Assessment of various factors and cultivars characteristics of the raw grains are of importance in the development of rice beverage.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.253-253
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• 2017

Recently, strong interest in the well-being and healthy food trends lead a spreading of rice processing products such as rice noodles, rice breads, and rice cakes. However, most of rice varieties developed in Korea showed very limited processing properties in processing of noodles compare to that of wheat flour. Moreover, low competitiveness as a raw processing materials due to high price give poor evaluations for rice noodles processing. To cope those barriers, 'Saemimyeon' a Tongil type high yielding variety with a high amylose contents was developed in RDA. 'Saemimyeon' showed about 10~32 % of increase in yield as 7.08MT/ha and 26.7% of high amylose contents together with easy grinding property of 65.7% of high chalkiness ratio. The both of milled as well as brown rice of 'Saemimyeon' were well fit for processing properties in rice pasta where the contents of rice flour for rice pasta was 99% (1% of Tapioka starch was intermixed in to the rice flour). A spaghetti type for wet noodles and macaroni type for dry noodles were developed, respectively. Each of pasta were showed relatively more or less an equal quality and panel test compare to that of durum wheat pasta products. Finally, rice pasta products could suggest an alternative idea for a new rice processing items where rice noodles market was stagnant.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1065-1070
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• 2015

A high-yield Korean rice cultivar cv. Boramchan and Hanmaeum, and rice cultivar for use in staple cv. Hopum were prepared and investigated for their physiological characteristics. Water content, water holding capacity, amylose content, damaged starch content, particle size, and pasting properties of the rice flours were measured. Moisture content of the Boramchan and Hanmaeum, made under wet and dry milling conditions, were as follows: wet conditions (14.79% and 13.56% respectively) and dry conditions (7.98% and 7.14% respectively). Water holding capacity of the Boramchan and Hanmaeum made by wet milling condition was 236.67% and 231.35%, respectively. Water holding capacity of the samples made by dry milling condition showed a higher score compared with other samples. The amylose content of Hopum, Boramchan, and Hanmaeum made by dry milling condition were 19.12%, 19.55% and 19.59%, respectively. Damaged starch contents of the samples made by wet milling showed a lower score. Final viscosity of Hopum, Boramchan, and Hanmaeum made by wet milling condition was 2,604, 3,052, and 2,917 cp, respectively. In this study, the results indicated that the super-yield Korean rice flour made by wet milling condition tends to show a lower water holding capacity, damaged starch contents and particle size, as compared to controls. However, a setback of the super-yield Korean rice flour was a higher score as compared to the controls, regardless of the milling conditions.