• 한국조리학회지
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• 제23권1호
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• pp.95-102
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• 2017

This study was activity of ${\alpha}-amylase$, glucoamylase of liquid Nuruk prepared using liquid Nuruk (NK) and Aspergillus kawachii (AK), Aspergillus niger (AN), Aspergillus oryzae (AO), Monascus kaoliang (MK). To investigate the relationship between the enzymatic activity and the total sugar content of liquid Nuruk depending on the types of Nuruk molds and the degree of rice-polishing. The activity of ${\alpha}-amylase$ depending on the types of Nuruk molds was shown to be 8.82, 8.72 units/mL in AN and AK treatments in brown rice liquid Nuruk at 24 hours after incubation, as the degree of rice-polishing increased, the activity of ${\alpha}-amylase$ was significantly lower (p<0.05). When brown rice was incubated in AN, it showed 8.83 units/mL at 48 hours after incubation, which was the highest activity, but there was no significantly difference (p<0.05), as the degree of rice- polishing was higher, the activity of ${\alpha}-amylase$ was lower. The activity of glucoamylase depending on the degree of rice-polishing showed 3,013 units/mL in AO treatment in brown rice liquid Nuruk at 24 hours after incubation, and the enzymatic activity was significantly higher (p<0.05). As the degree of rice-polishing increased, the activity of glucoamylase decreased, so liquid brown rice Nuruk showed the highest enzymatic activity, liquid white rice Nuruk was the lowest enzymatic activity. The highest enzymatic activity appeared in liquid Nuruk with brown rice at 48 hours after incubation. The activity of ${\alpha}-amylase$, glucoamylase showed higher enzymatic productivity as the degree of rice-polishing was lower, and there was an inverse correlation with the total sugar content.

• 한국식품과학회지
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• 제28권5호
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• pp.959-964
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• 1996

동진 품종의 현미를 2분도미, 5분도미, 7분도미로 도정하여, 도정도에 따른 쌀의 수화와 쌀가루의 이화학적 성질 및 호화 특성을 조사하였다. 쌀의 도정도가 증가하면 일반성분 중에서 단백질, 회분, 지방질, 섬유소의 함량이 감소되고, 쌀의 수분 증가량은 감소되고 SEM으로 관찰하였을 때 틈이 점점 현저하였다. 도정도가 증가할수록 쌀가루의 물결합능력, 팽윤력과 용해도는 증가하였다. 아밀로그람에서의 초기 호화온도는 도정도가 증가할수록 낮아졌고 최고점도, breakdown과 consistency는 높아졌다.

• 분석과학
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• 제37권1호
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• pp.12-24
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• 2024

In this study, laser-induced breakdown spectroscopy (LIBS) was used to estimate the degree of rice polishing. As-threshed rice seeds were dehusked and polished for different times, and the resulting grains were analyzed using LIBS. Various atomic, ionic, and molecular emissions were identified in the LIBS spectra. Their correlation with the amount of polished-off matter was investigated. Na I and Rb I emission line intensities showed linear sensitivity in the widest range of polished-off-matter amount. Thus, univariate models based on those lines were developed to predict the weight percent of polished-off matter and showed 3-5 % accuracy performances. Partial least squares-regression (PLS-R) was also applied to develop a multivariate model using Si I, Mg I, Ca I, Na I, K I, and Rb I emission lines. It outperformed the univariate models in prediction accuracy (2 %). Our results suggest that LIBS can be a reliable tool for authenticating the degree of rice polishing, which is closed related to nutrition, shelf life, appearance, and commercial value of rice products.

• 한국작물학회지
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• 제49권6호
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• pp.468-471
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• 2004

추청벼 등 4품종의 현미를 4.0, 6.4, 8.0, 9.6, $12.0\%$로 도정하여 벼의 도정율과 미강 중의 tocooienol 및 tocopherol 그리고 vitamin I 함량과의 관계를 구명하고자 본 시험을 수행한 결과는 다음과 같다. 1. 미강의 tocotrienol 함량이 최대가 되는 도정율은 4품종 각각 다른 반응을 보였으나 공통으로 가장 높았던 도정율은 6.4\%$이었고 추청벼와 안다벼는 도정율 $8.0\%$에서도 유의차가 없었다. 2. 미강의 tocopherol 함량은 4품종 모두 도정율 $8.0\%$에서 가장 높게 나타났으며, 일품벼 고시히카리 안다벼 3품종은 $9.6\%$에서도 유의차가 없었다. 3. 미강의 vitamin E함량이 가장 높은 도정율은 $8.0\%$이나 실험 품종들 간에 다소 차이는 있으나 대체로 $6.4-9.6\%$의 도정율에서는 유의차가 없었다. 4. 쌀의 tocotrienol, tocopherol 그리고 vitamin E함량은 도정율이 높아질수록 감소되는 경향으로 도정율 $8\%$일때 각각의 함량은 11.0, 8.2, $19.2 mg{\cdot}kg^{-1}$이었고, 쌀에는 tocotrienol과 tocopherol 동족체 중 $\alpha-$와 $\gamma-$가 검출되었다.

• 한국식품영양과학회지
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• 제4권1호
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• pp.97-100
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• 1975

Degree of polished rice so called 70 percentage of polished rice sold at the 19 places of rice dealer's store in Gwang - Ju city were surveyed through the New M.G.color reaction reagent, from 24th to 30th of January, 1975. The results were as follows ; 1. Nearly the 70 percentage polished rice sold at the rice dealer's store showed some differences in the degree of polishing of rice, with respect to color reaction in comparison with standard 70 percentage polished rice. 2. There have been no rice which are over excessive 70 percentage polished rice. 3. The place were more than 90 percentage of 70percentage polished rice amount, were 3 places in the 19 places rice dealer's store and 50 percentage of below 70 percentage polished rice amount were 8 places in the 19 places.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.46-50
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• 2003

In order to develop a new variety of rice that adapts to the climate of Aomori prefecture and possesses characteristics suitable for production of high quality Japanese sake, artificial cross experiments were executed between Yamadanishiki, which is widely used nationwide as an authentic variety of rice for sake production, and Hanafubuki, which was peviously developed by Aomori prefecture. An excellent hybrid, named Hanaomoi, was selected and fixed by a series of selection experiments and systematic cultivation. Unpolished Hanaomoi rice contained less amount of protein than Yamadanishiki and Hanafubuki. Unpolished rice of Hanaomoi was harder than Yamadanishiri and Hanafubuki, therefore polishing treatment was done in high yield and one could obtain a high degree of polish on the rice(namely 40% polishing). These features are advantageous to production of high quality of sake.Test brewing using 40% polished Hanaomoi gave rise to a characteristic sake that contained a slightly higher amount of alcohol and flavor components than Yamadanishiki and Hanafubuki. Sensory tests concluded that sake from Hanaomoi was as superior as the one from authentic Yamadanishiki. Hanaomoi is a promising variety of rice suitable for production of a high quality sake exclusive to Aomori prefecture.

• 한국식품과학회지
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• 제15권2호
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• pp.160-163
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• 1983

1. ${\alpha}$화 보리쌀의 끓는 물중에서의 수분흡수율은 호화도의 증가에 따라 증가하는 경향이며, 열탕처리구에서 현저하게 증가하고 가압솥처리구에서 가장 낮았으나 모두 무처리구 보다는 증가하였다. 2. ${\alpha}$화 보리쌀로 취반하고 그의 물성을 측정한 결과, 경도는 정백도가 높을수록 낮았으며, 가압솥 처리구가 가장 낮았고, 무처리구는 모두 높았다. 3. ${\alpha}$화 보리쌀 20%와 쌀 80%로 혼합취반하여 관능 검사한 결과 질감은 S-60에서 현저히 높았고 색깔에서는 모든 ${\alpha}$화 시료가 낮게 평가되었으나 총점에서는 무처리구와 유의적인 차이가 없었다.

• 공업화학
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• 제10권3호
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• pp.438-444
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• 1999

국내에서 생산되는 현미겨는 약 8.4~14.7 wt %의 지질을 포함하고 있으나 지방산의 양이나 조성은 현미겨의 형태, 토질 상태, 도정과 같은 전처리나 정미도에 영향을 받는다. 현미겨에 포함되어 있는 지질은 보통 palmitic acid, linolenic acid, linoleic acid, oleic acid, stearic acid, tocopherol, squalene 등과 같은 지방산으로 나눌 수 있다. 본 연구에서는 초임계유체를 이용하여 현미겨에서 squalene을 함유한 지방산을 추출하였으며, 각각의 공정에 ethanol을 첨가하여 초임계유체 추출을 시행하였다. 추출물은 GC-MSD로 분석을 하였고, 추출된 현미유의 양은 공정 온도, 압력에 따라 달랐으며, 조성은 초임계 이산화탄소의 환산밀도 (${\rho}_{\gamma}$ reduced density)에 영향을 받았다. 4시간의 공정시간에 약 70~80%의 현미유가 추출되었으며, ethanol을 첨가한 초임계유체 추출은 일반 초임계유체 추출에 비해 추출시간이 단축되며 동시에 추출량이 증가됨을 알 수 있었다. 또한 용매추출 공정에서 검출되지 않았던 squalene이 초임계유체 추출과 ethanol올 첨가한 초임계유체 추출에서 추출됨이 확인되었다.

• 생명과학회지
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• 제28권3호
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• pp.314-319
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• 2018

본 실험은 청청과 낙동 조합을 약배양하여 육성한 120 계통을 이용하여 식미치 관련 알칼리붕괴도에 대한 QTLs를 분석하고 탐색된 QTLs 유전자에 위치한 DNA 마카를 선발하여 기존 품종에 적용하여 다음과 같은 결과를 얻었다. CNDH 계통을 이용하여 알칼리붕괴도 변이를 조사한 결과 통일형 품종인 청청과 자포니카형 품종인 낙동 현미는 각각 1.9, 1.6를 보였으며 CNDH 계통은 $3.79{\pm}2.01$를 보였으며 변이 분포는 7.0-1.0까지 분포하였다. 모부본인 청청과 낙동 백미는 각각 5.6, 4.1를 보였으며 CNDH 집단의 평균은 $4.86{\pm}1.55$ 보였으며, 변이 분포는 7.0-2.0까지 분포하였다. 변이 분포 곡선은 비정규분포에 가까운 연속변이를 나타내었다. QTLs 분석에서 현미 1,2 반복에서 qBRA2, qBRA6, qBRA11, 백미 1반복에서 qHRA2-1, qHRA2-2, qHRA2-3, qHRA3, qHRA8, 2반복에서 qHRA2-1, qHRA2-2, qHRA2-3, qHRA3, 4반복에서 qHRA5으로, 이들은 각각 2번, 3번, 6번, 8번, 11번 염색체상에 탐색되었다. 현미, 백미 각 염색체상의 qBRA2, qBRA6, qBRA11의 표현형 변이는 1-9% 분포되었다. 알칼리붕괴도 관련 QTLs 분석 결과에서 탐색된 9개 marker를 토대로 모부본인 청청, 낙동을 기준으로 자포니카형 12품종, 인디카형 6품종에 다형성을 분석하였다. 밴드양상으로 크기에 차이를 보이는 분리비에 적합한 11번 염색체 RM27258을 선발하였다. 이상의 연구결과는 앞으로 미질이 좋은 벼 품종 개발하는데 기초자료로 이용 될 것 이다.

• 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.