• Preventive Nutrition and Food Science
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• 제3권3호
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• pp.234-240
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• 1998

This study attempted to determine the effect of various thawing methods and storage periods on the quality of froen cooked rice. Frozen cooked rice was thawed at four different methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature after 10 days, 30days and 90 days frozen storage. We conducted a physico-chemical analysis (moisture content, dehydration rates, degree of gelatinization, color value and texture) and sensory evalution on the frozen-thawed cooked rice. The study showed that there were no significant differences on the quality characteristics of frozen-thawed cooked rice during the storage period of 90 days. However, the thawing method of pressure cooking caused high moisture content, rapid dehydration rates, and a high degree of gelatinization on the cooked rice. Thus, the desirabililty for the rice diminished becaused of the excess moisture content and the change of appearance and testure in the rice due to the high temperature. There were similiar quality characteristics to the cooked rice after forzen-thawing whether by conventional cooking or by microwave heating and just after cooking. Thawing at room temperature also caused a significant decrease in quality characteristics.

• 한국작물학회지
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• 제36권4호
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• pp.351-359
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• 1991

우리나라에서의 미곡의 유통은 통일계와 일반계는 구분되어 이루어지고 있으나 식미가 다른 품종간에는 대부분 구분되지 않고 혼합되어 관리ㆍ유통되고 있다. 그러나 쌀의 식미는 품종간에 차이가 크고 국민들은 양식미쌀을 선호하므로 저식미쌀에 찹쌀, 또는 고식미쌀을 일정비율 혼합하여 식미향상효과를 얻을 수 있는지와 밥맛이 다른 품종들의 쌀을 일정비율로 혼합했을 때 밥맛에 미치는 영향을 밝히고자 하였다. 시료는 1987년 및 1989년산 통일계벼, 1990년 고성 및 부여산 일반계, 1989년산 통일계 삼강벼. 일반계낙동벼. 1990년산 추청벼, 동진벼 및 진부10호를 식미관능검사 1주일 전에 12분게로 도정하여 사용하였고 시판되는 최고가의 이천쌀과 일반계 찹쌀 상품을 공시하였으며, 식미관능검사는 국립농산물검사소 검사반과 작물시험장 미질 검정실에 의해 실시하였다. 그 결과는 다음과 같이 요약된다 1. 저식미찰(일반계)에 시판 고식미쌀을 중량비 80%까지 혼합하여도 식미향상은 없었으나 동진벼쌀(고식미)을 80% 혼합했을 때에는 동진벼쌀과 동등한 평점을 얻는 식미향상효과가 있었다. 중식미쌀에 시판 시판 고식미쌀을 80% 혼합한 경우는 식미가 크게 향상되었다. 2 식미가 불량한 통일계 고미('87, ＇89년산)에 시판되는 일반계 찹쌀상품을 20% 혼합하였을 때 식미가 향상되었으나, 중하위 식미의 통일계 중상위 식미의 일반계쌀에는 찹쌀 20% 혼합시에도 유의적 효과가 인정되지 않았다. 3. 중위 및 상위 식미품종인 낙동벼, 동진벼, 추청벼 간 여러가지 비율로 혼합한 경우 단일품종과 비교하여 일정한 경향의 유의적 식미 변화가 인정되지 않았다.

• Journal of Ecology and Environment
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• 제31권3호
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• pp.213-223
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• 2008

The increasing area of abandoned rice fields could provide new opportunities for wetland restoration in Asia. However, it is unknown how quickly or completely abandoned rice fields will recover from agricultural disturbances. We assessed water quality and plant community succession in abandoned rice fields with different hydrology in a mountain valley to understand the effects of hydrological regime on recovery. Water level, soil redox potential, water quality, plant composition, and primary production were measured. The sites, coded as D6, N13, and N16, had been recovering for 6, 13, and 16 years by 2006. N13 and N16 have been recovering naturally whereas D6 has been drained with a nearby dike and was tilled in 2001. The typical hydroperiods of D6, N13, and N16 were no surface water, permanently flooded, and seasonally flooded, respectively. The major change in vegetation structure of both D6 and N13 was the replacement of herbaceous species by woody species. Drawdown accelerated this change because Salix koreensis grew better in damp conditions than in flooded conditions. Phragmites japonica reduced plot-level plant species richness. The removal efficiency of $NH_4-N$, $NO_3-N$, and $PO_4-P$ from water varied seasonally, ranging between -78.8 to 44.3%, 0 to 97.5%, and -26.0 to 44.4%, respectively. In summary, abandoned rice fields quickly became suitable habitat for native wetland plant species and improved regional water quality. Variation among our sites indicates that it is likely possible to manage abandoned rice fields, mostly through controlling hydrology, to achieve site-specific restoration goals.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2002년도 창립 10주년 기념 국제학술심포지움
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• pp.86-98
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• 2002

When the quality and cooking characteristics of wash free rice was compared with those of control milled rice during storage, smaller quality change during storage and more easy to cook was found in wash free rice than control. The wash free rice equipment manufactured in foreign country was carefully investigated and commercial wash free rice equipment with 1metric ton per hour capacity was made considering the characteristics of domestic rice cultivar. Modification of the equipment was made through the repeated field test, and the technique on wash free rice equipment was transferred to the RICETECH. These systems were manufactured in RICETECH will be exported to China next year.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2002년도 창립 10주년 기념 국제학술심포지움
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• pp.72-85
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• 2002

When the quality and cooking characteristics of wash free rice was compared with those of control milled rice during storage, smaller quality change during storage and more easy to cook was found in wash free rice than control. The wash free rice equipment manufactured in foreign country was carefully investigated and commercial wash free rice equipment with 1metric ton per hour capacity was made considering the characteristics of domestic rice cultivar. Modification of the equipment was made through the repeated field test, and the technique on wash free rice equipment was transferred to the RICETECH. These systems were manufactured in RICETECH will be exported of China next year.

• 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.

• 한국토양비료학회지
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• 제45권5호
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• pp.671-675
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• 2012

본 연구는 2008년부터 2010년까지 경기도 여주군 능서면 오계2리 SCB 액비를 시용한 논에서 수질환경 부하 저감을 위한 물관리 방안을 제시하고자 시험을 수행하였다. 첫째, 액비가 시용된 경지정리된 논에서는 시용 직후부터 이앙 후 3주까지 물 흘러대기를 금지하여 시용된 양분의 환경부하를 최소화하면서 시비효율을 높이는 방안, 둘째, 액비를 최소 이앙 20일 전에 시비하여 토양 중 양분 보유 능력을 높여 작물의 양분 이용효율을 높이는 방안, 셋째, 액비 살포 후 바로 경운시 담수심을 5 cm내외로 유지하여 환경부하 저감 및 용수절감 효과를 높이는 방안, 넷째, 액비 중에 포함되어 있는 분변성 대장균은 논에 시용 후 48시간 후부터 소멸되기 시작하므로 최소 2일 동안 물꼬를 막아 논 표면수의 유출을 억제하여 대장균에 의한 인근 하천 수계 오염을 저감하는 방안이 있다. 그러나, 본 연구에서는 SCB 액비를 시용하는 평탄지 논에서 수행한 연구결과로 물관리 패턴이 다른 곡간지 논에서는 한계점이 있을 것으로 생각되나 액비를 시용하는 논은 대부분 시용이 용이한 경지정리된 평탄지 논으로 본 연구결과들은 외부 수질환경 부하를 방지하기 위한 영농지도 자료로 활용될 수 있을 것으로 생각된다.

• 한국식품조리과학회지
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• 제27권6호
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• pp.681-689
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• 2011

Yakkong germinated for 48 h at $23^{\circ}C$(48G), which showed the highest isoflavone content, was prepared with no heat treatment(48G-NH) or with additional heat treatment entailing 20 min boiling(48G-20B) or 15 min roasting(48G-15R). After being ground, each powder was substituted for rice flour by 10, 20, or 30% in rice cookies and compare with the control(100% rice flour cookies). The rice cookies containing 20 or 30% 48G-NH showed the highest crispness in texture and the lowest spreadability. The rice cookies containing 48G-20B and 48G-15R did not show a change in spreadibility, regardless of substitution level. For the rice cookies with 48G-15R, when the substitution level increased to 30%, the crispness decreased and hardness increased. The rice cookies with 48G-20B showed the lowest crispness regardless of substitution level. In terms of color, rice cookies substituted with Yakkong powder showed lower L and higher a* values than the control, however there were no tendencies related to b* value change. In sensory testing, rice cookies substituted with YK-48G had an improved quality, especially in flavor and texture as well as in function. The most acceptable substitution level was 20% of 48G-15R.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.10-10
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• 2022

The concern about food security is rising as the unstable situation of food supply and demand due to the Covid-19 pandemic, climate change, and turbulent political situation. Korea's global food security index (GFSI), analyzed by the Economist Group, is considered good, but the level continuously decreases in comparing food security levels by country. In particular, Korea is highly dependent on food imports, and food and grain self-sufficiency rates continuously decrease. Therefore, increasing those rates to strengthen food security is urgent. Among the major grains, the self-sufficiency of wheat, com, and soybeans, except rice, is relatively low. Unlike the decrease in the annual rice consumption, the annual wheat consumption has been continuously maintained or increased, which is required public-private efforts to increase the self-sufficiency rate of wheat. Applying the government's policies implemented to increase the self-sufficiency rate of rice in the past will help increase the self-sufficiency rate of wheat. In other words, expanding wheat production and infrastructure, stabilizing supply and demand, and establishing a distribution system can be applied. However, the processing capability of wheat and rice is different, which is necessary to improve wheat quality and processing technology to produce consumer-preferred wheat-based products. The wheat and flour quality can be improved through breeding, cultivation, post-harvest management, and milling. In addition, research on formulation, processes, packaging, and storage to improve the quality of wheat-based products should be done continuously. Overall, food security could be strengthened by expanding wheat production and consumption, improving wheat quality, and increasing wheat self-sufficiency.

• 한국식생활문화학회지
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• 제16권4호
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• pp.323-329
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• 2001

쌀엿강정은 쌀을 호화 건조하여 유탕처리하거나 가압 등으로 팽화시켜서 제조한다. 이때 호화과정에서 가열기구나 호화의 정도가 쌀의 팽화에 영향을 미칠 것으로 판단되어 이들 처리에 따라 팽화량(크기, 비중), 사진촬영, 주사형 전자현미경(SEM)으로 관찰 비교하였다. 1. 전기밥솥이나 압력솥, 혹은 증기로 찌는 등 밥의 형태로 쌀을 호화시킨 것은 팽화쌀이 서로 부착된 것이 많아 좋지 않았다. 전기밥솥이나 압력솥의 경우는 팽화쌀의 표면에 파괴된 부분이 나타났다. 압력솥이나 증기고 찌는 경우는 쌀의 팽화량이 작았다. 2. 쌀을 세정하여 바로 많은 양의 물로 끓이는 방법이 좋았으며, 쌀을 불려서 끓이는 방법과 팽화량에 차이를 보이지 않았다. 쌀을 불리더라도 익을 정도로만 단시간에 끓일 경우에는 오히려 팽화량이 작았다. 3. 쌀을 끓이는 시간이 길수록 팽화는 컸으나 너무 지나칠 정도로 끓일 경우에는 쌀의 표면이 파괴되거나 균열이 생겨서 외관이 좋지 않고 팽화량도 작았다.