• 한국식품과학회지
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• 제27권5호
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• pp.690-696
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• 1995

수분함량(12.6, 18.4, 24.4%)이 다른 벼를 각각 도정하여 pin mill로 분쇄한 건식쌀가루와 물에 침지후 roll mill로 분쇄한 습식쌀가루의 특성을 비교하였다. 벼수분 24%에서 건식제조된 쌀가루에서는 지방과 회분함량이 다른 건식쌀가루에 비하여 낮았다. 벼의 수분함량이 많을수록 건식쌀가루는 미세하게 분쇄되었고 전분입자가 떨어져나간 흔적이 쉽게 관찰되었다. 또한 백색도와 수분흡수지수가 높았고, 수분용해도지수는 낮았다. 벼수분이 많을수록 amylogram에서의 setback값은 낮았다. 건식제분된 쌀가루들은 gel consistency와 gel strength에서 차이가 없었으나 습식제분된 쌀가루에서보다 덜 consistent하였고, gel strength는 낮았다. 호화후 $7{\sim}14$일 저장하였을 때 노화gel을 재호화시키는 데 필요한 enthalphy는 벼수분이 많은 건식쌀가루일수록 높았고, 습식쌀가루의 경우는 건식쌀가루보다 낮았다.

• 한국식품조리과학회지
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• 제13권1호
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• pp.64-69
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• 1997

벼 8품종의 현미와 백미로 쌀빵을 제조하여 쌀빵가공성에 대한 벼 품종간 및 현 백미간 비교를 실시하고 관련특성간 상관관계를 살펴 보았다. 벼 품종간에는 제빵성의 차이가 있으나 현미와 백미간에는 유의한 차이가 없었다. 그러나 품종에 따라서는 현미와 백미간에 쌀빵특성의 현저한 차이를 나타내었다. 찰벼 품종인 한강찰벼는 백미로는 쌀빵의 제조가 불가능하였으나 현미로는 다른 어떤 품종 보다도 제빵성이 우수한 결과를 얻었다. 메벼 품종들 중에서는 AC 27, IR 44, 수원조가 백미의 제빵성이 우수하였고, 이 세 품종을 제외하고는 모두 백미보다 현미로 쌀빵을 만들 경우 가공특성이 좋은 경향이 있었다. 쌀의 일반성분 및 쌀빵의 제 특성 간의 상관성을 현미와 백미에 대해 별도로 살펴보면, 현미의 경우에는 부피 증가율이 큰 쌀빵 반죽일수록 푹신한 감이 있는 쌀빵 제조가 가능하였고, 촉촉한 쌀빵일수록 부드럽고 응집성이 높은 경향이었다. 백미의 경우에는 단백질 함량이 낮을수록 촉촉한 느낌의 쌀빵이 되는 경향이었으며, 지질함량이 높을수록 기공의 크기가 작고 균일하며 탄력성이 적은 쌀빵이 제조되는 경향이 있었다 또한 쌀빵 성형이 양호할수록 경도 및 씹힘성이 낮은 부드러운 빵이되는 경향이었으며, 기공의 크기가 균일할수록 기공의 크기가 작으면서 푹신한 감이나 탄력성이 낮은 빵이 되는 경향이었다.

• 한국식품영양과학회지
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• 제26권5호
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• pp.886-891
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• 1997

The interrelation between physicochemical properties of milled rice and retrogradation of rice bread during cold storage was examined to compare the varietal difference in maintenance of rice bread quality. Twelve rice materials showed big varietal difference on physicochemical properties of rice starch such as amylose content(0.0~29.2%), gel consistency(20~98mm), and alkali digestion value(2.0~7.0). Rice bread made from milled rice of Jungwonbyeo, AC 27 and IRAT 177 exhibited soft texture and late retrogradation of rice bread during cold storage(4$^{\circ}C$). The amylose content of milled rice was closely associated with gel consistency negatively and with springiness of rice bread positively. The retrogradation of rice bread texture during cold storage was correlated with gel consistency of rice flour positively and with alkali digestion value of milled rice negatively.

• 한국분말재료학회지
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• 제2권2호
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• pp.135-141
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• 1995

As the first step of study on fabrication of ceramic powders from phytoliths in rice, especially in rice husks, pulverization method of rice husks and the properties of milled rice husks were investigated. Impact methods, such as ball milling, were not meaningful for pulverizing elastic and thin fabric structure of rice husks. The most effective one was cutting method. In the present work, a rotating knife cutting method was applied to pulverizing rice husks. A 40-mesh screen was inserted under the rotating knives. The most portion of the milled powder was found in -50/+100 mesh section. Morphology of the milled rice husks revealed that the husks larger than 70 mesh were flake-like shape, at -70/+100 mesh section relatively equi-axed shape, at -170/+325 mesh section rod-like shape, and below 325 mesh section dust-like shape. Tap density of raw rice husks was about 0.1 $g/cm^3$, while those of milled rice husks were over $0.4 g/cm^3$. This meant that, for a given volume of reactor, raw material charge can be increased more that 4 times when using milled rice husks than unmilled one. True densities of unmilled and milled rice husks were higher than $1.4 g/cm^3$, and increased with decreasing milled sizes.

• 한국식품과학회지
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• 제20권3호
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• pp.392-398
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• 1988

드럼건조시 습식제분한 것은 슬러리 수분함량 60%이상, 건식제분한 것은 슬러리 수분함량 80%이상이 적정 하였으며 이 때의 호화도는 92% 이상이었다. 아밀로그램이나 리올로지 특성은 건식제분보다는 습식제분하여 제조된 알파미분이 우수하였으며 슬러리 수분함량이 높을수록 WAI값은 증가하고 WSI값은 강소하였다. 색도에서는 건식제분보다는 습식 제분 처리구에서 백색도가 높았으며 슬러리 수분함량이 증가할수록 알파미분의 백색도가 증가하였고 황색도는 감소하였다. 미세구조 관찰에서는 슬러리 수분함량이 높을수록 망상구조를 많이 형성하였다. 또한 반죽기능성은 건식 제분보다 습식제분 처리구에서 MTI가 높게 나타났다.

• Journal of Biosystems Engineering
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• 제28권2호
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• pp.137-142
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• 2003

The water conditioning experiments of brown rice were performed to analyze the variation of the milled rice recovery using a continuous type conditioner at Jin-ju, Yeo-ju, and Yong-in RPC(Rice Processing Complex). About 8,000 kgf, 6,000 kgf and 10,000 kgf of the brown rice of 13-14 %(wb) initial moisture contents were used as experimental materials at Jin-ju, Yeo-ju, and Yong-in respectively. The broken rice and rice bran were collected and weighted to calculate the milled rice recovery. The amounts of broken rice with water conditioned occurred lower than that of broken rice without water conditioned. And the milled rice recovery of water conditioned ones were increased as 1.22%, 0.87%, and 1.00% compared with those of the non water conditioned ones at Jin-ju, Yeo-ju. and Yong-in respectively. Especially, the result of the experiments of Jin-ju RPC showed that about 33% and 35% of total increased milled rice recovery were the portion of the moisture content increment and the broken rice reduction respectively.

• Journal of Biosystems Engineering
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• 제30권4호
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• pp.242-248
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• 2005

There was no useful milling standard to produce high quality milled rice efficiently and adequately in Rice Processing Complex. Therefore, the whiteness of milled rice produced Rice Processing Complexes were different according to Rice Processing Complexes and milling periods at the same Rice Processing Complex. This research was carried out to contribute the production and distribution of high quality milled rice through determination of whiteness condition of milled rice as a milling stndard based on degree of bran removal using New $May-Gr\ddot{u}wald$ reagent dyeing method and taste of cooked rice. The optimum whiteness value of milled rice for efficient milling in Rice Processing Complex was found to be from 40 to 41, while the degree of milling was from $8.9\%\;to\;9.2\%.$ At this whiteness condition, the first derivative of whiteness value according to degree of milling was higher than the average value from brown rice to well milled rice, and the broken kernel ratio was from $3.0\%\;to\;3.4\%.$ This whiteness condition ($40\~41$) could be considered as a milling condition in Rice Processing Complex.

• 한국식품영양과학회지
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• 제34권3호
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• pp.414-419
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• 2005

실온 이상의 온도(40, 50, 50℃)에서 햅쌀과 저장 쌀을 가온 수침하여 습식제분한 쌀가루의 특성을 조사하였다. 습식처리한 쌀가루는 모두 30% 이상의 수분을 지니고 있었으며, 60℃에서 수침을 한 쌀가루가 40℃, 50℃수침에 비해 수분 함량이 높게 나타났다 쌀가루의 L값은 햅쌀로 제조한 쌀가루에서 약간 높았으며 황색도를 나타내는 b값은 저장 쌀이 햅쌀 백미로 만든 쌀가루보다 높게 나타났다. 햅쌀과 저장 쌀 모두에서 쌀가루의 WAI, WSI 및 gel consistency는 수침 온도가 증가함에 따라 증가하였다 Amylograph peak viscosity, hot paste viscosity, 그리고 cold paste viscosity 모두 수침온도가 증가함에 따라 증가하였으며 특히 저장 쌀 시료에서 보다 큰 폭으로 증가하였다. DSC호화개시온도 및 호화정점온도는 수침온도가 높아짐에 따라 증가하였고, 호화엔탈피는 감소하는 경 향을 보였다. 쌀가루의 입도 분석 결과 저장 쌀이 햅쌀로 제조한 쌀가루에 비해 작은 경향을 보여주었으며 햅쌀의 경우 수침온도가 60℃, 50℃, 40℃순으로 입도분포가 큰 경향을 보여주었다. SEM에 의한 쌀가루의 미세구조 관찰 결과 수침 온도의 증가에 따라 입자 크기의 증가와 손상된 쌀가루 표면이 관찰되었다.

• 한국작물학회지
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• 제44권3호
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• pp.288-295
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• 1999

Nineteen japonica and Tongil-type rices were selected from seventy nine Korean and Japanese rice cultivars grown in 1989 based on the water uptake behavior of milled rice under the room temperature and boiling conditions. The selected rice cultivars were investigated for water absorbability and some physicochemical characteristics of milled rice, proper water amount for cooking and sensory evaluation of cooked rice. The relationships among the tested grain properties were also examined. The highest varietal variation of water uptake rate was observed at twenty minutes after soaking in water. The maximum water uptake of milled rices at room temperature occurred mostly at about eighty minutes after soaking in water. Newly harvested rices showed a significantly lower water uptake rate of milled rice at 20 minutes after soaking, a relatively higher maximum water absorption ratio under the room temperature, and the less water uptake and volume expansion of boiled rice compared with the one-year old rice samples. 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 ansd 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 averaged to 2.63(in v/v basis). The water amount needed for optimum cooking was the lowest in Cheongcheongbyeo (Tongil-type rice) and the highest in Jinbubyeo, and the amount could be estimated with about 70% fittness by the multiple regression formula based on some water uptake characteristics, ADV and amylose content of milled rice as the independent variables. Nineteen rice cultivars were classified into seven groups based on scatter diagram projected by principal component analysis using eight properties related to water uptake and gelatinization of milled rice.

• Journal of Biosystems Engineering
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• 제21권2호
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• pp.198-207
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• 1996

To measure the moisture content, protein and viscosity of brown and milled rice with Near Infrared Reflectance(NIR) analyzer, the comparison and analysis of the data from the chemical analysis and NIR analyzer were conducted. The purpose of this study is to find out the fundamental data required for the prediction of rice qualify and taste rank, and to develop a measuring method of constituents and physical characteristics of domestic rice with NIR analyzer. The important results can be summarized as follows. 1. The $r^2$ and SEC of moisture calibration from brown rice powder were 0.87 and 0.09 respectively, those of milled rice powder were 0.95 and 0.08 respectively. 2. The $r^2$ and SEC of protein calibration from brown rice powder were 0.83 and 0.20 respectively, those of milled rice powder were 0.86 and 0.20 respectively. 3. The $r^2$ and SEC of viscosity calibration from brown rice powder were 0.36 and 15.50 respectively, those of milled rice powder were 0.55 and 12.98 respectively. Further study is required to develop better prediction model for viscosity. It is necessary the continuous study including wavelength selection, because $r^2$ is small for practical use. 4. The regression equation for one rice variety was nearly coincident with other. Therefore, it is required that the prediction model should be developed for the all rice samples.