• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.528-537
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• 1996

Qualify changes of microwave-reheated cooked rice aseptic-packaged with different lid materials and oxygen absorbers were determined during storage at $20^{\circ}C,\;30^{\circ}C$ and $40^{\circ}C$. Springiness cohesiveness and adhesiveness increased as storage temperature increased, while gumminess and hardness decreased. Lid materials oxygen absorbers, and storage temperatures showed no significant effect on the textural properties of cooked rice after microwave reheating. Degree of gelatinization was increased as storage temperature increased and was restored after microwave reheating. Scanning electron micrograph showed that the surface of cooked rice became rough and hollowed after microwave reheating for 1.5 min, indicating starch was regelatinized, while there was no difference with respect to lid materials. Photomicrographs of the cross-section of aseptic-Packaged cooked rice showed that a compact and solid structure increased and retrogradation occured in starch as storage temperature decreased, while a compact and solid structure was decreased and starch was regelatinized after microwave reheating.

• Journal of Biosystems Engineering
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• v.11 no.2
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• pp.66-75
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• 1986

In order to improve the traditional post harvest system in Korea, a model for mechanized grain drying and storage facilities was developed. Also, a computer program for the model system was developed. For the study, flat type steel bin and circulation type dryer were selected for the model and Fortran language was used for the computer program. This program was tested by using various practical data. The following results were obtained from the study: 1. The general model developed can be used for designing a rough rice drying and storage facility within the range from 100 ton to 1000 ton capacity. 2. Major output of the computer program for designing a model system were as follow; a. The dimension of the plant. b. The storage bin size, dryer number and dryer size. c. The dimension of individual equipment and its required HP. d. Capital requirement and operating cost of the model system.

• Food Science and Preservation
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• v.24 no.7
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• pp.908-914
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• 2017

Cold plasma (CP) was applied to examine microbial safety and physicochemical properties of rough rice. CP was generated in a square-shaped plastic container (250 W, 15 kHz, ambient air) and dielectric barrier discharge plasma treatment was applied for periods of 0, 10, and 20 min during 2 weeks at 4 and $25^{\circ}C$. As a result of observing changes in growth of microorganisms, 3.46-3.86 log CFU/g of total aerobic bacteria and 2.27-2.86 log CFU/g of mold were detected in the early stage of storage. The growth of total aerobic bacteria and mold was increased depending on the storage temperature and period, but there was no big difference between cultivars. Microbial analysis after storage showed that microorganisms of plasma-treated group were less grown approximately 1.50 log CFU/g. Moisture content of rough rice was decreased by storage temperature and periods. As for the amylose content, changes in the content by plasma were not observed in Samkwang, Cheongpum and Misomi, whereas Palbangmi showed a tendency to increase. The results of this study indicated that CP treatment improved the microbial quality of rough rice, but further studies should be conducted to reduce the deterioration of sensory quality induced by CP.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.360-365
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• 2003

미곡종합처리장은 개소 당 평균 30억이 투자되는 방대한 시설로 수확된 산물상태의 벼를 수집ㆍ건조ㆍ저장ㆍ가공 및 포장공정이 일괄적으로 처리되는 농업의 첨단기술이 결집된 시설이라 할 수 있다. 미곡처리장은 약 80개의 단위기계와 100여종의 부대시설로 구성되어 있다. 미곡종합처리장은 거의 모든 과정이 중앙제어기에 의해 제어 가능하다. 그러나 미곡종합 처리장의 상온통풍건조시설은 기상조건, 투입벼의 함수율 및 반입량에 따라서 송풍기와 히터의 운전방법을 달리해야 하며, 또한 투입벼의 함수율에 따라서 벼의 퇴적고를 달리해야 하는 등 시설의 운전에 세심한 주의가 필요하다. (중략)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.375-379
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• 2007

This study was carried out to examine the effects of storage duration on physico-chemical properties of milled rice. Rough rice of three rice ecotypes(Japonica, Tongil and F1 hybrids with Tongil back-ground) was stored for 4, 16, 28 and 40 months without artificial environmental control in seed warehouse. And this materials were investigated for seed germination rate, brown rice hardness, alkali digestion value(ADV), contents of protein, amylose, total sugar, and reducing sugar. Seed germination rate was significantly reduced with storage duration increased regardless of rice ecotypes : 66.7% from 16 months storage, 2.5% from 28, and nil from 40 months storage in Japonica rices. And 54.0%, 67.9% in Tongil, and F1 hybrid after 40 months storage, respectively. Brown rice hardness was not significantly affected by storage duration but showed significant genotypic differences. As the storage duration prolonged, sugar content and alkali digestion value increased, protein content declined while amylose content did not show clear tendency. Total and reducing sugar contents showed sharp increase upto 16 months storage and thereafter steady in crease, and the percentage of reducing sugar content out of total sugar content increased with extended storage duration.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.136-140
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• 1976

To investigate the preservability of Tongil, three types(rough, brown and milled rice) of Tongil and the common variety (being composed of typical varieties) in Korea were stored at a ambient and a low temperature $(15^{\circ}C)$ warehouse from April to October of each year for three years (1972-1974). The results obtained are described as follows; 1) Temperatures of atmosphere and the natural temperature warehouse changed in the same way. 2) Similar changes of relative humidity were observed in atmosphere and both warehouses. 3) Equilibrium moisture content of Tongil at $25^{\circ}C$ was 0.55 % lower in rough and brown rice. 0.33% lower in milled rice than each type of the common variety. 4) Weight loss rate in the natural temperature storage and in the low temperature storage was 1.35% and 0.74% after 6 month storage. 5) The change of fat acidity in browe rice was greater than any others (rough and milled rice). 6) Hardness of Tongil was 1.64kg higher than that of the common variety. 7) Germination rate was about the same during the low temperature storage, but that of brown of the natural temperature storage was abruptly decreased to $23%{\sim}37%$ after August. As a result, it is possible Tongil is applicable to the long-term storage of rice due to Tongil's superior preservability.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.69-69
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• 2017

Due to the lack in storage facility, considerable amount of rice is stocked in the open air, which causes increased stale flavor and deteriorates palatability and merchantable quality. Lipoxygenase-3(LOX-3) is involved in the production of volatile constituents in stored rice, and the development of stale flavor is delayed in LOX-3 null rice. LOX activity in the rice grain is localized in bran fraction and the tropical Japonica cultivar 'Dawdam' was reported that the absence of LOX-3 is inherited as a simple recessive trait. Also, it was reported that the peroxidation of unsaturated fatty acids occurs at lower levels in the 'Dawdam' bran fraction during storage than in rice varieties with LOX-3. This study was conducted to develop LOX-3 null rice lines using 'Dawdam' and investigate changes of physicochemical properties of the lines stored at different storage temperatures and periods. So we analyzed texture, toyo glossiness value, germination rate and lipoxygenase activity of 15 LOX-3 null rice lines on the condition of which rough rice had been stored at different temperatures (high temperature condition at $35^{\circ}C$ and low temperature condition at $15^{\circ}C$ for 4months. Hardness and stickiness of the lines tendered to be increased when it was stored at high temperature and adhesiveness, springiness, cohesiveness and chewiness was not considerably different according to storage temperatures and periods. The germination rate of HR29062-B-98-2-1-B among LOX-3 null rice lines was higher than another lines, 99.3, 94.0% after 4months stored at low temperature and high temperature, respectively. The lipoxygenase activity was 3,304, 1,601unit/mg protein after 4months stored at low temperature and high temperatures, respectively. So, it is thought that this line will be useful to breed rice varieties with high storability after tested on agricultural traits.

• Korean journal of food and cookery science
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• v.27 no.4
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• pp.47-54
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• 2011

This study was performed to investigate the quality characteristics of Yakpyun with added brown rice. The Yakpyun was prepared with polished rice, brown rice, Jujube paste, Makkolli, sugar and salt. The Yakpyun was made with various levels (0, 20, 40, 60 or 80%) of added brown rice. After making the Yakpyun, it was examined for the effect of adding brown rice on quality characteristics using scanning electron microscopy (SEM), a mechanical test, and a sensory evaluation. The moisture contents of Yakpyun tended to decrease with increasing amounts of added brown rice, but no significant differences were observed. As the content of brown rice increased, the lightness (L) decreased and redness (a) and yellowness (b) increased. In a texture profile analysis, hardness decreased with increasing brown rice content from the moment of production to 3 days of storage. When more brown rice was added, rough surfaces were found more often under SEM, and large holes were evident between granules. The results of the sensory evaluation showed that overall acceptability was the highest for Yakpyun containing 40% added brown rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.29-35
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• 2007

This study was conducted to investigate the germination rate, fat acidity and lipoxygenase activity of brown rice after storage of 6 and 12 weeks at high temperature ($35^{\circ}C$) with fifteen Korean and two Japanese rice varieties. Germination rate in rough rice and palatability value in cooked rice by rice taster were lower with longer storage period, while protein content, fat acidity, and lipoxygenase activity in brown rice were higher with longer storage period. Fat acidify was negatively correlated with germination rate. However fat acidity was positively correlated with lipoxygenase activity. Seventeen varieties were classified into two groups on the basis of germination rate, fat acidity and lipoxygenase activity after 12 weeks' storage at high temperature; Group I including eleven varieties of Odaebyeo, Sangmibyeo, Unkwangbyeo, Ilpumbyeo, Nampyeongbyeo, Ilmibyeo, Donganbyeo, Jungsanbyeo, Koshihikari, Hitomebore and Chucheongbyeo showed high germination rate, low fat acidity and low lipoxygenase activity, while Group II including six varieties of Sindongjinbyeo, Hoanbyeo, Gyehwabyeo, Daeyabyeo, Hopyeongbyeo, and Dongin 1 showed lower germination rate, high fat acidity and high lipoxygenase activity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.339-349
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• 2010

The uses of the polypropylene bulk bags having the loading capacities more than 500 kg are increasing in Korea recently as a storage container for rough rice. This study was performed to obtain the basic information on the changes of temperature and relative humidity in the bulk-bag-stored high moisture rough rice during waiting for drying. At the moisture content more than 22% on wet weight basis of paddy, the bulk-bag inside temperature rose up to more than $40^{\circ}C$ and then slid down during storage. For example, in case of Hwaseongbyeo, 26.5% moisture content of rough rice (MCRR) harvested at 46 days after heading (DAH) showed $54.5^{\circ}C$ of peak temperature at 66.8 hours after bulk-bag loading, 22.5% MCRR harvested at 52 DAH exhibited $42.0^{\circ}C$ at 81.1 hours, and 19.7% MCRR harvested at 55 DAH displayed $38.9^{\circ}C$ at 119.0 hours. There were a good linear relationship between peak temperatures of bulk-bag inside and moisture contents of paddy ($r^2$=0.89 in 2005, and 0.87 in 2006), while the slope and intercept of the linear regression equation was affected by the environmental conditions such as ambient temperatures and microbial flora. The peak temperatures increased with the rate of about $2.74-3.33^{\circ}C$ per every 1% increase of moisture content at higher moisture contents of paddy than 19%. The relative humidity varied depending on bulk-bag inside temperature and rough rice moisture content, and showed the range of 94.2% to 99.9% in the central point of the bulk-bag. The results suggested that a rapid drying treatment as soon as possible was needed to produce a good quality of rice when the paddy of high moisture more than 22% on wet basis was harvested in a bulk-bag especially at high ambient temperature.