• Journal of Biosystems Engineering
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• 제27권1호
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• pp.51-58
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• 2002

The goal of this research was to an optimum conditions for the brown rice conditioning from data of milling characteristics after conditioning of the brown rice. The range of the initial moisture content of the sample was 13%, 14%, and 15%, the range of the increment of the moisture content was 0.4% and 0.8% with respect to the initial moisture content, and a ripe time after conditioning was eight hours. The results obtained from this research can be summarized as fellows. 1 The crack ratio after conditioning the brown rice with the initial moisture content was increased as the initial moisture content decreased and increment of the moisture content increased. The crack ratio of the milled rice was increased than that of the non-conditioned brown rice and decreased with the conditioned brown rice with the increment of the moisture content of 0.4% and 0.5%. 2. The broken rice ratio after conditioning the brown rice with the initial moisture content was a little higher than that of the non-conditioned brawn rice. The broken ratio of the conditioned brown rice with the increment of the moisture content of 0.4% was increased around 0.2∼0.4% with respect to the non-conditioned brown riced and the broken ratio of the brown rice was high with increased amount of water sprayed during conditioning process. 3. The moisture content of the milled rice after conditioning the brown rice with the initial moisture content increased around 0.3∼0.8% with respect to the non-conditioned milled rice. 4. The electric energy consumption on milling process with the conditioned brown rice by the initial moisture content was decreased 3.4∼39.1% with respect to the non-conditioned brown rice.

• 한국작물학회지
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• 제34권4호
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• pp.384-389
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• 1989

한국산 미곡 통일형과 자포니카형의 형태적 특성을 구명하기 위하여 1986년에 3개 작물시험장(수원, 밀양 및 이리)에서 생산된 통일형 13품종과 자포니카형 10품종을 공시재료로 하여 다음과 같은 결과를 얻었다. 천입중은 벼, 현미, 백미 모두 두 형간에 유의성이 없었으나 벼와 현미의 무게 차 즉 왕겨층의 무게와 현미와 백미의 무게 차 즉 미강층의 무게에서는 각각 P<2.859** 및 4.316***으로 유의성을 보였으며 왕겨층은 통일형이 미강층은 자포니카형이 컸다. 벼, 현미 및 백미의 입폭은 두 형간에 각각 P<5.189***, 5.289*** 및 5.988*** 그리고 입장은 각각 P<3.016**, 4.419*** 및 5.492***으로 유의성을 보였으며, 입폭과 입두께는 자포니카형이 통일형보다 두꺼웠고, 입장은 통일형이 길었다. 입폭/입두께의 비에서 벼는 두 형간에 P<2.396*으로 유의성이 있었으나 현미와 백미는 유의성이 없었다. 입장/입폭비는 벼 : P<5.525***, 현미 : P<5.495***, 백미 : P<5.863***, 입장/입두께 비는 벼 : P<4.734***, 현미 : P<6.863***, 백미 P<8.425***로 유의성을 보였으며 이들 비는 모두 통일형이 컸다.

• 한국식품조리과학회지
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• 제11권1호
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• pp.51-57
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• 1995

The effect of milling on the nutrients of raw and parboiled rice grain samples was investigated. Parboiling treatments of choo chung paddy decreased head rice yields and pressure parboiling proved to be more beneficial in reducing white belly rice. Except PP sample mean length/width ratio of parboiled milled rice kernels(8% milling degree) were more larger than raw milled rice and the extent depended on severity of parboil heat treatment. Parboiling had no effect on the protein content of browm rice(0% milling degree) but increased in 4%, 8% milling degree and in PL40 sample. Parboiled rice had a lower fat and the extent depended on degree of milling. Ash content of parboiled brown rice decreasd compared to raw brown rice and generally decreased according to milling degrees were high. Nevertheless, PP, PT40 and PL40 parboiled milled rice samples(0% milling degree) contained more ash than raw milled rice. Parboiling increased total sugar and reducing sugar and increased according to milling degrees were high. Parboiled rice had a high reducing sugar content than raw rice except for PT sample, and more contained as higher milling degree. Total amino acid content of parboiled brown rice increased compared to raw brown rice except for PL40 sample. Parboiled rice of 4% milling degree had a lower total amino acid content and then 8% milling degree had a higher than raw rice. Ca content of parboiled rice was lower than raw rice and tended to have lower as milling degree were high. Parboiled rice of 0 and 4% milling degree had a lower Fe content degree but higher in 8% milling degree. PP and PT40 samples contained more Fe than any other parboiled rice. Parboiled milled rice contained more thiamin than raw milled rice. Rice of milling degree 6% and PL sample contained most thiamin.

• 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.

• Journal of Biosystems Engineering
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• 제32권1호
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• pp.1-5
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• 2007

This study was conducted to find out effects of abnormal kernels of 0 to 30% in brown rice on quality characteristics during milling using friction type test mill. The average hardness values of abnormal and normal brown rice kernels were 6.52 kg$_f$, 8.48 kg$_f$, respectively. According to the increase of abnormal kernels in brown rice, grain temperature, required electrical energy, the broken kernels ratio, and the weight of solid matter on the surface of milled rice were increased due to crush of the abnormal kernels during milling, which proves that abnormal kernels in brown rice should be removed before milling to improve milling characteristics.

• Plant Resources
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• 제6권2호
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• pp.134-139
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• 2003

This study was conducted to investigate the relationships between yearly variations of meteorological elements and yearly variations of productivity in rice. In addition, correlation coefficients among yield and yield components were used to find out the relationships between meteorological elements and productivity. Yearly variation of the mean air temperature in May was large with coefficients of variation(C.V.) of 25.0%, but the variation of the duration of sunshine in May were relative small. No. of panicles per hill and 1,000 grains wt. of brown rice were great with C.V. of 21.1, 19.7%, respectively, brown rice yield show more or less C.V. of 5.5% and milled rice show still less variation. Correlation coefficients between temperatures in period of cultivation from May and yield were positive correlations. Correlation Coefficients between precipitation in period of cultivation from Sep. to Oct. and yield are positive correlations. Correlation coefficients amount the panicle length, no. of panicles, no. of spikelets, ratio of ripened grains, 1,000 grains wt. of brown rice, milled rice yield, brown rice yield and milled rice yield were positively significant at the level of 1 %, respectively.

• 한국식품영양학회:학술대회논문집
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• 한국식품영양학회 2001년도 동계 학술심포지움
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• pp.39-74
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• 2001

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s∼1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great, progress and success was obtained in development of high-quality japonica cultivars and qualify evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice caltivars and special rices adaptable for food processing such as large kernel, chalky endosperm aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer. 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 and 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 average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic mcroscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high Probability of determination. The ${\alpha}$ -amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice bread. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

• 한국작물학회지
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• 제57권1호
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• pp.35-40
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• 2012

본 연구는 현미의 새로운 가공법 개발을 위하여 현미의 과피층을 0%, 5%, 및 10%를 도정하여 이에 따른 현미의 단백질 및 총 식이섬유 함량변화를 조사하였다. 그리고 쌀의 품질 특성 조사를 위하여 과피층 제거 정도 따른 알칼리붕괴도(ADV)를 조사하고 현미밥의 경도, 끈기, 인성 및 부착성을 측정하였다. 그 결과, 설갱벼를 제외하고 과피층이 감소할수록 현미의 단백질 및 총 식이섬유 함량이 감소하는 경향을 나타내었다. ADV는 삼광벼가 과피층 제거에 의하여 유의적으로 증가하는 경향을 나타내어 과피층 제거에 의하여 호화가 용이해질 것으로 판단된다. 또한 현미밥의 기계적 식미치를 측정한 결과, 백진주벼 및 큰눈벼의 경도 및 인성은 감소하였고, 백진주벼, 큰눈벼, 설갱벼의 끈기 및 부착성은 증가하였다. 그리고, 과피층 제거에 의하여 백진주벼<삼광벼<큰눈벼 순서로 부착성-경도 비율이 증가하는 결과를 보였다. 따라서 밥맛이 따라서 과피층의 부분적인 도정이 현미의 품질 및 식감을 향상시킬 것으로 기대된다.

• 농업과학연구
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• 제44권3호
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• pp.416-423
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• 2017

This study aimed to identify milling characteristics depending on the rotating speed of the main shaft of the cutting-type rice milling machine which can minimize the conventional milling process. Brown rice, which was produced in Gunsan-si, Jeollabuk-do, Republic of Korea, in 2016, was used as the experimental material. The milling characteristics of white rice were measured under four different rotating speeds of main shaft: 950 - 1,050 rpm, 1,000 - 1,100 rpm, 1,050 - 1,150 rpm, and 1,100 - 1,160 rpm. For each shaft speed, 300 kg of brown rice was processed, and the milling characteristics were measured according to the whiteness, grain temperature, cracked rice ratio, broken rice ratio, turbidity, and energy consumption. The whiteness of rice grain was found to be consistent at around $40{\pm}0.5$ only when milled at the shaft speed of 950 - 1,050 or 1,000 - 1,100 rpm. The grain temperature during the milling process increased by 11.35 to $11.85^{\circ}C$, showing little differences amongst shaft speeds. The cracked rice ratio increased by 8.2 to 10.4% at all conditions. The broken rice ratio ranged from 0.58 to 0.76%, reflecting a low level. The turbidity after milling was 54.8 ppm when milled at 1,000 - 1,100 rpm. Energy consumption of 12.98 and 12.18 kWh/ton were recorded at the shaft speed of 1,000 - 1,100 and 1,050 - 1,150 rpm, respectively. The result of this study indicates that the optimal rotating speed of main shaft would be 1,000 - 1,100 rpm for a cutting-type rice milling machine.

• 한국작물학회지
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• 제59권2호
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• pp.174-180
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• 2014

등숙기 일조부족이 수량 및 수량구성형질, 쌀의 이화학적 특성 및 식미치에 미치는 영향을 분석하고자 자연광을 대비하여 35%, 55% 차광 처리한 결과는 다음과 같다. 1. 등숙기 차광처리에 의해 미품, 호품, 신동진의 등숙률, 현미천립중, 쌀 수량은 감소하였고 차광정도가 클수록 높은 감소율을 보였다. 2. 차광처리시 백미 단백질 함량은 증가하였고 35% 차광보다 55% 차광에서 높았으며, 미품이 호품과 신동진에 비해 단백질 함량의 변화가 적었다. 3. 차광처리시 아밀로스 함량 변화는 없었으나 식미치는 차광정도가 높을수록 감소하였고 미품이 신동진과 호품에 비해 변화가 적었다. 4. 차광에 의해 최고점도, 최저점도, 최종점도 및 강화점도는 낮아지고 호화온도와 치반점도는 높았다.