• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2002년도 창립 10주년 기념 국제학술심포지움
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• pp.109-119
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• 2002

Rice production in Korea began to rise significantly after 1970. Rice is the dominant food in Korea and most of the rice production (about 95%) is consumed as cooked rice. it provides over 4,000Kj of energy per capita per day. Apparent rice availability in 2000, 93.6Kg of milled rice per person annually. The non-allergenic character of rice offers a sound basis for development of products for markets for all age groups. Whole grains are washed rice, coated rice, enriched rice in Korea. Utilization of rice as food can be categorized three categories in Korea; direct food use, processed foods, and brewing. Rice for direct consumption include regular whole grain, precooked rice, brown rice and specialty products such as aseptic cooked rice, retort cooked rice and rice burger. Rice used for processed foods includes that for cereal, soup, baby food, snack, cake, noodle, brown rice tea, and minor unclassified uses. Rice use for brewing is for the production of fermented rice wine. The use of rice for direct food is by for the greatest of the three uses. Although direct food accounts for the largest domestic consumption, a significant quantity of rice is used in processed products. The use of rice by-products as human food should not be over looked. Utilization of by products(rice germ, rice bran) requires a specialized technology. Typical type of rice is black rice. When cooked, black rice gives a black color to cooked rice. Glutinous rice performs specific functions in several commercial products such as dessert, gravis, cake and snack. Rice starch production is quite limited because of the high cost of making of starch. Rice processed products in Korea are occupied small parts of total rice production compared to Japan. Rice cake (Garadog) is the principal from of rice product consumed in Korea. Rice cake and snack is usually prepared from non-glutinous milled by washing, grinding, steaming, cooling and packaging. Rice cake will be continued to be a major rice product in Korea. Rice products represent a means to study variety differences in rice grain quality, since the processing magnifies differences not normally detected from more boiling. Recently, rice processing companies in Korea are about 400 ones which uses rice about 160,000tons. New rice processed products and modified traditional products must be developed and diversified with high quality and processing properties of rice processed products are improved.

• 한국작물학회지
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• 제37권3호
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• pp.244-249
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• 1992

벼 품종간 미립 절대밀도의 변이와 그에 영향하는 미립관련형질들을 구명하기 위하여 통일형 30, Japonica형 72 및 Indica형 133 계 235 품종에 대해 미립의 절대밀도와 모양 및 크기, 경도, 심복백, ADV, amylose 함량, 전분구조를 조사하고 그들 간의 관계를 검토한 결과는 다음과 같다. 1. 백미의 절대밀도는 평균적으로 통일형 1.496g/$cm^3$, Japonica형 1.506g/$cm^3$, Indica형 1.500g/$cm^3$이었고, 출수까지의 생육일수 및 현미의 경도와는 정의 상관을 심복백, 현미의 부피 및 1000립중, 입장과는 부의 상관을 보였다. 2. 편회귀분석 결과 미립의 크기가 절대밀도에 가장 크게 영향하는 것으로 나타났다. 3. 절대밀도의 고, 저에 따른 전분결정구조의 차이는 감별할 수 없었으며, 심복백의 경우 정상배유부분에 비해 전분립자가 둥글고 그 결정조직이 느슨하였다. 4. 미립의 크기가 비슷하고 심복백이 없는 경우 절대밀도의 품종간 차이는 미미한 것으로 나타나서 수량성에는 크게 영향하지 못할 것으로 생각되나, 미질의 측면에서는 검토되어져야 할 것이다.

• 한국식품과학회지
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• 제21권5호
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• pp.613-618
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• 1989

한국산 미곡 통일계 및 일반계 품종들의 미질특성을 구명하기 위하여 1985년에 3개 작물시험장(수원작물시험장, 영남작물시험장 및 호남작물시험장)에서 생산된 통일계 13품종과 일반계 10품종을 재료로 하여 백미의 취반특성 및 밥의 texture 특성을 조사하였다. 취반특성 중 흡수율 및 취반시 사용한 용액 중 용출고형물은 각각 $p<2.172^*$ 및 $p<2.419^*$로 계통간에 유의차를 보였는데 흡수율은 일반계가 통일계보다 높았으며, 용출고형물은 통일계가 일반계보다 높았다. 밥의 texture 특성에서 hardness와 cohesiveness는 $p<4.370^{***}$ 및 $p<2.371^*$로 계통간에 유의성이 인정되었으며, hardness는 일반계가, cohesiveness는 통일계가 높았다. Amylose 함량과 adhesiveness 사이에는 통일계에서 $r=-0.922^{**}$ 일반계에서 $r=-0.915^{**}$으로 역상관을 이루었으며, 단백질 함량과 hardness 사이에는 통일계에서 $r=0.954^{**}$, 일반계에서 $r=0.915^{**}$로 정상관을 이루었다.

• 한국식품과학회지
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• 제52권4호
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• pp.396-402
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• 2020

건식 제분용 쌀가루 전용 품종인 한가루와 밥쌀용 품종인 삼광의 호화특성을 비교해 가공특성을 확인해 본 결과 한가루가 삼광에 비해 노화 안정성이 높고, 호화 중 열, 전단에 대한 저항성이 낮아 가공특성이 좋을 것으로 확인되었으나, 조지방, 조단백 함량이 삼광에 비해 높아 저장 시 주의를 해야 하는 것으로 나타났다. 호화특성은 상온 저장 시 12개월 저장 시 두 품종 모두 변화하였고, 그로 인해 가공특성이 변할 것으로 예상되었다. 한가루는 상온 저장 시 지방산가의 변화도 크게 나타나서 식미권장기준 보다 높은 지방산가를 나타냈다. 하지만 저온 저장을 하게 되면 두 품종 모두 호화특성을 초기와 유사하게 유지가 가능했으며, 한가루는 지방산가의 변화도 감소하여 식미권장기준에 적합하게 유지되었다. 가공특성은 우수하지만 저장성이 좋지 않은 건식 제분용 쌀가루인 한가루는 저온 저장하여 저장성도 높일 수 있고, 가공특성도 저장 전과 유사하게 유지될 수 있는 것을 확인할 수 있었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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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.

• Journal of Biosystems Engineering
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• 제1권1호
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• pp.15-15
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• 1976

In analyzing the operational characteristics of a rice whitening machine, the internal radial pressure of the machine was measured using strain gage equipment. Changes in cylinder and feed screw configurations, screen type, cylinder speed and counter-pressure levels were examined to determine their impact on the quality and quantity of milled rice and the performance of the machine. The results are summarized as follows: 1. The internal radial pressure in the whitening chamber varied with the surface condition of the grain being processed. During the first or second pass through the machine, pressure was relatively low, reached a maximum after two to three passes with combinations I and II, three to six with combination III and then began to fall. 2. The pitch of the feed screw and the size of the feed gate opening which determine the rate of entry of grain into the whitening chamber, appeared to be the most important factor aff-::cting the degree of radial pressure, quality and quantity of milled rice and the efficiency of the machine. Using a feed screw with a wide pitch (4.8cm), radial pressure was relatively high and head rice recovery ratio \vere quite low. In this case capacity and machine effic?iency were much higher than obtained when using a feed screw with a narrow pitch (2.3cm). Very significant responses in radial pressure, head rice recovery rates and machine capacity were observed with changes in cylinder speed and counter-pressure levels when using the wide pitch feed screw. 3. The characteristics of the screen which surrounds the whitening chamber had an important effect on whitening efficiency. The existence of small protuberances on the original screen resulted in significant increases in both machine capacity and efficiency but without a significant decrease in head rice recovery or development of excessive radial pressure. Further work is required to determine the effects of screen surface conditions and the shape of the cylinderical steel roller on the rate of bran removal, machine efficiency and recovery rates. The size of the slotted perforations 0:1 the screen affects total milled rice recovery. The opening size on the original screen was fabricated to accommodate the round shape of Japonica rice varieties but was not suitable for the more slender Indica type. Milling Indica varieties with this screen resulted in a reduction in total milled rice recovery. 4. An increase in cylinder speed from 380 to 820 rpm produced a positive effect on head rice recovery for all machine combinations at every level of counter-pressure used in the tests. Head rice recovery was considerably lower at 380rpm using a wide screw pitch when compared to the results obtained at speeds from 600 to 820 r.p.m. The effects of cylinder speed On radial pressure, capacity and machine efficiency showed contrasting results, depending on the width of the feed screw pitch. With a narrow feed screw pitch (2.3cm), a direct proportional relationship was observed bet?ween cylinder speed and both radial pressure and machine efficiency. In contrast, using a 4.8 centimeter pitch feed roller produced a series of inverse relationships between the above variables. Based on the results of this study it is recommended when milling Indica type long grain rice varieties that the cylinder speed of the original machine be increased from 500-600 rmp up to a minimum of 800 rpm to obtain a greater abrasive effect between the grain and the screen. The pitch of the feed screw should be also reduced to decr?ease the level of internal radial pressure and to obtain higher machine efficiency and increased quality of milled rice with increased cylinder speeds. Further study on the interaction between cylinder speed and feed screw pitch is recommended. 5. An increase in the counter pressure level produced a negative effect On the head rice recovery with an increase in radial pressure, capacity, and machine efficiency over all combinations and at every level of cylinder speed. 6. Head rice recovery rates were conditioned primarily by the pressure inside the whitening chamber. According to the empirical cha racteristics curve developed in this study, the relationships of head rice recovery ($Y_h$) and machine capacity ($Y_c$/TEX>) to internal radial pressure ($X_p$) followed an inverse quadratic function and a linear function respectively: $$Y_h^\Delta=\frac{1}{{1.4383-0.2951X_p^\ast+0.1425X_p^{\ast\ast}}^2} , (R^2=0.98)$$$$Y_c^\Delta=-305.83+374.37X_p^{\ast\ast}, (R^2=0.88)$$The correlation between capacity and power consumption per unit of brown rice expressed in the following exponential function: $$Y_c^\Delta=1.63Y_c^{-0.7786^\{\ast\ast}, (R^2=0.94)$$These relationships indicate that when radial pressure increases above a certain range (1. 6 to 2.0 kg/$cm^2$ based On the results of the experiment) head ricerecovery decrea?ses in a quadratic relation with a inear increase in capacity but without any decrease in power consump tion per unit of brown rice. On the other hand, if radial pressure is below the range shown above, power consumption increases dramatically with a lin?ear decrease in capacity but without significant increases in head rice recovery. During the operation of a given whitening machine, the optimum radial pressure range or the correct capacity range should be selected by controlling the feed rate and/or counter-pressure keeping in mind the condition of the grain, particulary the hardness. It was observed that the total number of passes is related to radial pessure level, feed rate and counter-pressure level. The higher theradial pressure the fewer num?ber of pass required but with decreased head rice recovery. In particular, when using high feed rates, the total number of passes should be increased to more than three by reducing the counter-pressure level to avoid decreaseases in head rice recovery (less than 65 percent head rice recovery on the basis of brown rice) at every cylinder speed. 7. A rapid rise in grain temperature seemed to have a close relationship with the pressure generated inside the whitening chamber and, subsequently with head rice reco?very rates. The higher the rate of increase, the lower were the resulting head rice recoveries.

• Journal of Biosystems Engineering
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• 제1권1호
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• pp.17-48
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• 1976

In analyzing the operational characteristics of a rice whitening machine, the internal radial pressure of the machine was measured using strain gage equipment. Changes in cylinder and feed screw configurations, screen type, cylinder speed and counter-pressure levels were examined to determine their impact on the quality and quantity of milled rice and the performance of the machine. The results are summarized as follows: 1. The internal radial pressure in the whitening chamber varied with the surface condition of the grain being processed. During the first or second pass through the machine, pressure was relatively low, reached a maximum after two to three passes with combinations I and II, three to six with combination III and then began to fall. 2. The pitch of the feed screw and the size of the feed gate opening which determine the rate of entry of grain into the whitening chamber, appeared to be the most important factor aff-::cting the degree of radial pressure, quality and quantity of milled rice and the efficiency of the machine. Using a feed screw with a wide pitch (4.8cm), radial pressure was relatively high and head rice recovery ratio \vere quite low. In this case capacity and machine effic\ulcorneriency were much higher than obtained when using a feed screw with a narrow pitch (2.3cm). Very significant responses in radial pressure, head rice recovery rates and machine capacity were observed with changes in cylinder speed and counter-pressure levels when using the wide pitch feed screw. 3. The characteristics of the screen which surrounds the whitening chamber had an important effect on whitening efficiency. The existence of small protuberances on the original screen resulted in significant increases in both machine capacity and efficiency but without a significant decrease in head rice recovery or development of excessive radial pressure. Further work is required to determine the effects of screen surface conditions and the shape of the cylinderical steel roller on the rate of bran removal, machine efficiency and recovery rates. The size of the slotted perforations 0:1 the screen affects total milled rice recovery. The opening size on the original screen was fabricated to accommodate the round shape of Japonica rice varieties but was not suitable for the more slender Indica type. Milling Indica varieties with this screen resulted in a reduction in total milled rice recovery. 4. An increase in cylinder speed from 380 to 820 rpm produced a positive effect on head rice recovery for all machine combinations at every level of counter-pressure used in the tests. Head rice recovery was considerably lower at 380rpm using a wide screw pitch when compared to the results obtained at speeds from 600 to 820 r.p.m. The effects of cylinder speed On radial pressure, capacity and machine efficiency showed contrasting results, depending on the width of the feed screw pitch. With a narrow feed screw pitch (2.3cm), a direct proportional relationship was observed bet\ulcornerween cylinder speed and both radial pressure and machine efficiency. In contrast, using a 4.8 centimeter pitch feed roller produced a series of inverse relationships between the above variables. Based on the results of this study it is recommended when milling Indica type long grain rice varieties that the cylinder speed of the original machine be increased from 500-600 rmp up to a minimum of 800 rpm to obtain a greater abrasive effect between the grain and the screen. The pitch of the feed screw should be also reduced to decr\ulcornerease the level of internal radial pressure and to obtain higher machine efficiency and increased quality of milled rice with increased cylinder speeds. Further study on the interaction between cylinder speed and feed screw pitch is recommended. 5. An increase in the counter pressure level produced a negative effect On the head rice recovery with an increase in radial pressure, capacity, and machine efficiency over all combinations and at every level of cylinder speed. 6. Head rice recovery rates were conditioned primarily by the pressure inside the whitening chamber. According to the empirical cha racteristics curve developed in this study, the relationships of head rice recovery ($Y_h$) and machine capacity ($Y_c$/TEX>) to internal radial pressure ($X_p$) followed an inverse quadratic function and a linear function respectively: $$Y_h^\Delta=\frac{1}{{1.4383-0.2951X_p^\ast+0.1425X_p^{\ast\ast}}^2} , (R^2=0.98)$$ $$Y_c^\Delta=-305.83+374.37X_p^{\ast\ast}, (R^2=0.88)$$ The correlation between capacity and power consumption per unit of brown rice expressed in the following exponential function: $$Y_c^\Delta=1.63Y_c^{-0.7786^\{\ast\ast}, (R^2=0.94)$$ These relationships indicate that when radial pressure increases above a certain range (1. 6 to 2.0 kg/$cm^2$ based On the results of the experiment) head ricerecovery decrea\ulcornerses in a quadratic relation with a inear increase in capacity but without any decrease in power consump tion per unit of brown rice. On the other hand, if radial pressure is below the range shown above, power consumption increases dramatically with a lin\ulcornerear decrease in capacity but without significant increases in head rice recovery. During the operation of a given whitening machine, the optimum radial pressure range or the correct capacity range should be selected by controlling the feed rate and/or counter-pressure keeping in mind the condition of the grain, particulary the hardness. It was observed that the total number of passes is related to radial pessure level, feed rate and counter-pressure level. The higher theradial pressure the fewer num\ulcornerber of pass required but with decreased head rice recovery. In particular, when using high feed rates, the total number of passes should be increased to more than three by reducing the counter-pressure level to avoid decreaseases in head rice recovery (less than 65 percent head rice recovery on the basis of brown rice) at every cylinder speed. 7. A rapid rise in grain temperature seemed to have a close relationship with the pressure generated inside the whitening chamber and, subsequently with head rice reco\ulcornervery rates. The higher the rate of increase, the lower were the resulting head rice recoveries.

• Journal of Biosystems Engineering
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• 제34권6호
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• pp.439-445
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• 2009

This study was performed to investigate the optimum abrasive and friction milling ratio. This was accomplished by determining changes in the quality, such as whiteness, moisture content, broken kernel, unstripped embryo rate, and surface characteristics or milling difference, during an abrasive and friction based milling process. When only abrasive was milled, the increase of whiteness was fast in the first milling, whereas the increasing rate of whiteness was small in the latter milling. The decreasing rate of moisture content and broken kernel increased as the friction milling ratio was increased. Combining with the friction milling was considered a suitable method because the unstripped embryo rate was high only when abrasive milling was used. In the case of a high abrasive milling ratio, a significant milling difference was observed in the initial milling. This indicated that the milling difference was not completely eliminated despite using friction milling in the latter milling. Consequently, it was necessary to minimize the milling difference in the initial milling. When milling quality was synthetically considered, the abrasive milling ratio was varied from 20~50%. When the abrasive milling ratio was greater than 40%, the external quality of the rice milled deteriorated since holes and defects generated on the surface in the initial milling were not removed. Due to this deterioration in surface characteristics, an abrasive milling ratio of 30% was identified as a suitable level.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2006년도 하계 학술대회 논문집
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• pp.198-201
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• 2006

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2006년도 하계 학술대회 논문집
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• pp.206-209
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• 2006