• Journal of Biosystems Engineering
• /
• 제24권4호
• /
• pp.309-316
• /
• 1999

This study was conducted to develop a large-scale rice polisher with double polishing stages for producing clean rice with high quality in rice processing complexs. The performance of the developed rice polisher was evaluated and improved. The results obtained from this study were as followings : 1. A large-scale rice polisher with double polishing stages was developed, which consisted of two polishing chambers(polishing part I and II), two spraying parts, a feeding part, power of 37kW, control panel, etc. Especially, the purpose of polishing part Iwere to uniformly mix white rice sprayed with water and to remove bran particles from the rice. the roller surface of the polishing part I was coated with chromium. 2. The capacity of the developed rice polisher was 4t/h. The broken rice rate of the polisher was less than 0.2%, compared with about 1% of others. 3. The whiteness increment of the developed polisher was 2.6~3.0% compared with about 2.3~2.5% of others. 4. The energy consumption of the developed polisher was 0.5kWh/100kg. 5. The developed polisher was improved with the angle change of screen slot of the polishing chamber I. The broken rice rate was reduced from about 0.5% to about 0.2% as the max. internal pressure of the polishing chamber II decreased by 0.4kg/$\textrm{cm}^2$ due to the increase of resistance in the polishing chamber I. The whiteness of the polisher showed more than 38~39. 6. The developed rice polisher showed high performance, compared with other domestic and foreign polishers.

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

• 한국조리학회지
• /
• 제23권1호
• /
• pp.95-102
• /
• 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.

• 분석과학
• /
• 제37권1호
• /
• pp.12-24
• /
• 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.

• Applied Biological Chemistry
• /
• 제35권6호
• /
• pp.475-478
• /
• 1992

습식연미 도정조건 및 습식연미 도정쌀의 특성을 구명하기 위하여 일반도정시 강층 제거량별 및 가습량별로 습식연미 도정시험을 실시하였던 바 도정 적정 습식연미 도정조건은 일반도정으로 강층을 95% 제거한 후 5% 가습 연미하는 것이 가장 좋았다. 그리고 습식연미 도정쌀이 일반도정쌀 보다 현백률은 0.75% 낮았으며, 수분함량은 같았으나 백도는 3.5%나 높았고, 윤기가 매우 좋았다. 그리고 쌀을 수세하여 용출된 고형물 및 취반용액 중 용출고형물은 각각 0.30 및 2%, 정도 낮았다. 또한 습식연미 도정쌀의 저장성도 일반도정쌀 보다 좋았다.

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

• Journal of Biosystems Engineering
• /
• 제23권3호
• /
• pp.245-252
• /
• 1998

The structural characteristics of a small scale rice polisher was analyzed to improve its performance. Spraying characteristic of nozzles used for rice polishing was also analyzed by a machine vision system. The internal pressure of the polishing chamber was measured according to outlet resistance, water spraying, and roller shaft speed. In addition, the performance of the rice polisher was evaluated to improve it in the basis of internal pressure in polishing chamber, whiteness, and broken rice ratio of clean rice according to the operating conditions. Actual nozzle discharge rate and drop size were 125 cc/min and 86~97 ${\mu}{\textrm}{m}$, respectively. In the case of water spraying on rices, the internal pressure showed 4.9~9.8N/$\textrm{cm}^2$ increase. broken rice ratio decreased, and there was no difference in whiteness. The internal pressure inueased up to two times with the increase of the outlet resistance. Also, the pressure at the upper part of screen was one and half times as high as the pressure at the lower part. In the case of water spraying rate of 150 cc/min, the roller shaft speed of 850 rpm resulted in no difference in whiteness and decrease of 0.3% in broken rice ratio, comparing to the roller shaft speed of 950 rpm.

• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 1998년도 하계 학술대회 논문집
• /
• pp.206-216
• /
• 1998

The structural characteristics of small scale rice polisher was analyzed to improve its performance. Spraying characteristic of nozzles used for rice polishing was also analyzed by a machine vision system. The internal pressure of the polishing chamber was measured according to outlet resistance, water spraying , and roller shaft speed. In addition , the performance of the rice polisher was evaluated to improve it in the basis of internal pressure in polishing chamber, whiteness , and broken rice ratio of clean rice according to the operating conditions. Actual nozzle discharge rate and drop size were 125cc/min and 86.97㎛, respectively. In the case of water spraying on rices, the internal pressure showed 4.9-9.8N/㎠ increase, broken rice ration decreased , and there was no difference in whiteness . The internal pressure increased up to two time with the increase of the outlet resistance. Also, the pressure at the upper part of screen was one and half times as high as the pressure at the lower part. In the case of water spraying rate of 150 cc/min, the roller shaft speed of 850 rpm resulted in no difference in whiteness and decrease of 0.3%in broken rice ratio, comparing to the roller shaft speed of 950 rpm.

• 한국식품과학회지
• /
• 제11권1호
• /
• pp.18-25
• /
• 1979

BHC를 살포하여 재배한 현미(玄米)(BHC잔류량 0.3 ppm)의 도정(搗精), 세미(洗米), 및 취반(炊飯)중 BHC 잔류량(殘留量)을 분석하여 그의 행방을 추적한 결과는 다음과 같다. 1) 현미의 도정(搗精)중 BHC는 10분도미에서 8%, 7분도미에서 20%가 잔류하였다. 2) 쌀의 세척(洗滌)중 10분도미에서는 34%, 7분도미에서는 31%가 잔류하였다. 3) 재래식 취반(炊飯)과 전기밥솥에 의한 취반중 10분도미에서는 각각 86%, 77%, 7분도미에서는 각각 69%, 41%가 잔류하였다. 4) 전체적으로 보아 현미로부터 밥으로의 BHC 이행률(移行率)은 10분도미에서 2.3%, 7분도미에서 4.3%에 불과하였다. 따라서 현미의 조리(調理), 가공(加工)중 발생되는 BHC의 제거량(除去量)을 잔류농약 허용량(許容量)설정에 반영(反映)하여 야 될 것이다.

• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 1997년도 하계 학술대회 논문집
• /
• pp.141-149
• /
• 1997

Structural characteristic of a rice polisher of small size was analyzed to improve its performance and to utilize such data in developing a rice polisher of large size. Spraying characteristic of nozzles which were used for rice polishing was evaluated by a machine vision system. Internal pressure of the polishing chamber was also measured according to outlet resistance, water spraying, and roller shaft speed. In addition, the performance of the polisher was analyzed based on whiteness and broken ratio according to operating conditions.