• 한국식품조리과학회지
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• 제14권3호
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• pp.219-224
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• 1998

Kochujang was prepared by using retrograded rice cakes (Song Pyun, Sym rice cake, Ssuk rice cake, Pat rice cake) as a source starch and the physiochemical and sensory characteristics were compared with traditional kochujang during aging for 60 days. Moisture content of all kochujang groups increased slowly but crude fat content decreased according to aging process. Changes of pH values of all kochujang reduced gradually during aging and the pH of saccharified kochujang was lowered than that of traditional one. Total reducing sugar contents in saccharified kochujang reached the maximum value at 50th day, and decreased thereafter. In contrast, the reducing sugar content in traditional kochujang was the highest at 30-day-aging. After 60 days of aging, the total contents of organic acids were 28.57 mg for P$\_$1/, 27.9 mg for P$\_$4/, 27.05 mg for P$\_$3/ 24.60 mg for P$\_$2/, and 22.30 mg for P$\_$0/. By sensory evaluation, saccharified kochujang prepared with Siru rice cake showed the highest sensory score in its appearance, flavor, texture, color, and taste.

• 한국식품과학회지
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• 제39권5호
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• pp.584-587
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• 2007

치환도를 달리한 하이드록시프로필화 쌀전분의 동적 레올로지 특성이 소변형 진동측정방법(small-deformation oscillatory measurement)에 의해 관찰되었다. Aging 전 $4^{\circ}C$에서 측정된 저장탄성률 G#과 손실탄성률 G"의 값은 치환도(0.030-0.118)가 증가함에 따라 증가하였으며, 반면에 tan ${\delta}5(G"/G#)$는 감소하였다 $4^{\circ}C$에서 10시간 aging하는 동안 하이드록시프로필화 쌀전분의 G#값은 초기 단계에서 급속히 증가한 다음 곧 바로 2시간이내에 안정기(plateau) 영역에 도달하였다. 그러나 천연전분(native starch)은 10시간 동안의 aging후에도 안정기 영역이 관측되지 않았다. 치환도의 증가는 하이드록시프로필화 쌀전분의 안정기 G#값의 감소를 초래하였다. Aging하는 동안의 구조전개 속도상수 K는 1차 kinetics식으로부터 얻어졌으며, 하이드록시프로필화 쌀전분의 K값은 높은 치환도에서 낮은 수치를 보여주었다.

• Applied Biological Chemistry
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• 제38권1호
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• pp.83-89
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• 1995

전통식 된장 제조방법으로 널리 이용되고 있는 메주의 염수침지 방법을 개량식 된장 제조방법의 전처리 과정에서 도입하여 제조한 쌀된장을 $32^{\circ}C$에서 숙성 시킨 것과 $15^{\circ}C$에서 30일 숙성 후 $32^{\circ}C$에서 30일 숙성시킨 것으로 구분하여 숙성기간에 따른 일반 성분과 미생물 균수 변화 및 색도를 측정한 결과는 다음과 같았다. 염수침지에 의한 침지식의 경우 숙성 기간에 따라 pH의 감소가 완만하였으나, 염수침지가 생략된 비침지식은 $32^{\circ}C$ 숙성 초기에 pH가 급강하 하여 숙성 60일후 pH 5.1의 수준을 보였다. 환원당의 변화는 전처리 방법 및 숙성온도에 관계없이 숙성 초기에 증가하여 숙성 $30{\sim}50$일에 최대치를 보인 후에 감소하였다. 수용성 질소, 포르몰태 질소, 암모니아태 질소 및 아미노태 질소 함량의 경우 저장온도에 따른 변화보다는 전처리 방법, 즉 염수침지 여부에 따른 변화가 더 컸다. 숙성이 완료된 된장의 색도는 전처리 방법에 따른 영향을 받을 뿐만 아니라 숙성온도에 따라 많은 차이를 보였다. 숙성기간에 따른 각 종류별 쌀된장의 세균수는 숙성온도에 따라 큰 변화가 없으나 진균수는 숙성온도에 따른 많은 차이점을 나타내었다. 이상의 결과로 보아 개량식 쌀된장 제조방법에 염수침지과정을 도입할 경우, 색도의 차이는 있으나 전반적으로 숙성기간 및 숙성온도에 따른 특성 변화가 적어 숙성과정에 의한 영향보다는 침지과정에 의해 쌀된장의 특성이 주도됨을 알 수 있었다. 또한 숙성초기의 질소화합물 함량이 매우 높으며, 이러한 경향은 숙성 60일까지 유지되어 결국 50일간의 염수침지 기간을 감안하더라도 개량식 쌀된장에 비해 짧은 제조기간으로 높은 숙성도를 유지할 수 있을 것으로 사료된다.

• 한국식품저장유통학회지
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• 제18권6호
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• pp.859-868
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• 2011

코지와 대두의 혼합비율을 달리하여 제조한 된장을 60일간 숙성하면서 품질을 비교 평가하였다. 대두와 현미코지의 비율은 1.5:1 (BR-1), 2:1 (BR-2), 3:1 (BR-3)로 하고, 대조구로써 대두와 백미코지를 2:1 (PR)로 하였다. 60일 숙성 후 수분과 염도는 시료 간에 큰 차이가 없었으나, 숙성 경과에 따라 pH, 산도 및 미생물수는 숙성 20~30일 째에 최대에 이르렀고. 이에 앞서 10~20일째에 환원당 함량과 에칠 알코올 함량이 최대로 증가하였으며 이러한 변화는 코지비율이 높을수록 빠르고 변화 값이 높은 경향이었다. 된장의 숙성지표가 되는 아미노태 질소 함량도 숙성 경과에 따라 증가하여 60일 숙성 후 BR-1이 가장 많은 887.6 mg%이었으며, 유리아미노산 함량도 BR-1이 가장 높아 $4047.0{\pm}1.5$ mg%이었으며, 코지비율이 높을수록 아미노산 생성이 많았다. GABA함량은 숙성 경과에 따라 소량 증가하는 것으로 나타났다. 색도는 숙성 경과에 따라 L값과 b값은 점차 감소하였으며 a값은 점차 증가하였다. 이와 같은 결과에서 현미코지를 이용한 된장은 백미코지를 이용한 된장에 비하여 숙성이 빠르게 진행되었고, 이와 함께 된장의 풍미를 결정하는 환원당, 에칠 알코올 및 아미노산의 함량이 상대적으로 다소 높게 나타났으며 이러한 변화는 숙성 30일 까지 뚜렷하게 나타남을 알 수 있었다. 이상의 결과에서 현미코지 된장은 백미코지 된장에 비하여 단백효소활성이 우수하므로 상대적으로 숙성이 빠르게 진행되며 에칠알코올과 아미노산 성분 등의 풍미물질이 많이 생성될 뿐만 아니라 현미의 영양성분이나 기능성물질인 GABA성분의 생성이 유도되어 산업적으로도 의미가 있는 것으로 생각되며, 현미코지 비율이 가장 높았던 BR-1이 품질면에서 바람직할 것으로 생각되었다.

• 한국식품과학회지
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• 제26권1호
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• pp.23-25
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• 1994

쌀의 소비를 촉진하고 쌀가공품의 하나인 쌀물엿을 이용한 고추장 제조를 시도한 결과 수분함량, pH 및 적정산도는 쌀물엿 고추장과 쌀가루 고추장 사이에 큰 차이를 보이지 않았다. 환원당은 쌀물엿 고추장이 쌀가루 고추장에 비하여 높았으며, 담금 초기에 비하여 숙성 90일에는 두 시험구 사이의 차이는 줄어들었다. 아미노태 질소는 숙성 80일까지는 증가하다가 그 이후에는 두 시험구 모두 감소하였다. 색도 측정 결과 쌀가루 고추장의 L값이 쌀물엿 고추장에 비하여 높게 나타났다.

• 한국식품저장유통학회지
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• 제24권4호
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• pp.491-496
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• 2017

Paddy rice is typically stored during postharvest until rice grain is processed into brown rice and milled rice by hulling and milling procedure, respectively. Recently, instead of storing paddy rice, storage of brown rice has been in the spotlight because it is more convenient and economically feasible. Different brown rice cultivars with varying amylose contents including waxy rice, medium-waxy rice, and non-glutinous rice were stored in room temperature storage for four months, and the changes in grain qualities of brown rice were evaluated. Amylose content significantly affected pasting properties in which rice cultivar with higher amylose content showed longer pasting time and higher peak viscosity. Storage also affected pasting viscosities, showing an increase in peak viscosity, but a decrease in breakdown viscosity. The changes in pasting viscosity during storage could be an important starch property for aged brown rice utilization. Waxy brown rice showed the weakest aging property in terms of free fatty acids (FFA) accumulation, whereas non-glutinous rice was more substantial grain quality against aging. The FFA values of two months storage were not significantly different from the initial FFA contents, suggesting that brown rice stored in room temperature for two months could be feasible for direct consumption of brown rice.

• Journal of Biosystems Engineering
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• 제40권2호
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• pp.124-136
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• 2015

Purpose: Grain quality is a general concept that covers many characteristics, ranging from physical to biochemical and physiochemical properties. Rice aging during storage is currently a challenge in the rice industry, and is a complicated process involving changes in all of the above properties. Spectroscopic techniques can be used to obtain information on the quality of rice samples in a non-destructive manner. Methods: The objective of this review was to highlight the factors that contribute to rice quality and aging, and to describe various spectroscopic modalities, particularly vibrational and hyperspectral imaging, for the assessment of rice quality. Results: Starch and protein are the main components of the rice endosperm, and are therefore key factors contributing to eating and cooking quality. While the overall starch, protein, and lipid content in the rice grain remains essentially unchanged during storage, structural changes do occur. These changes affect pasting and gel properties, and ultimately the flavor of cooked rice. In addition, grain quality is significantly affected by growing and environmental conditions, such as water availability, temperature, fertilizer application, and salinity stress. These properties can be evaluated using spectroscopic techniques, and rice samples can be discriminated by using multivariate statistical analysis methods. Conclusion: Hyperspectral imaging and vibrational spectroscopy techniques have good potential for determining rice quality properties in a non-invasive manner, i.e., not requiring the introduction of instruments into the rice grain.

• 한국생활과학회지
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• 제14권6호
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• pp.1037-1046
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• 2005

Using three consecutive years' harvested rices and their starches isolated from rice flours by alkaline method, it was found that no significant aging effect on rice flour and starch was observed based on following results. Proximate data of flours or starches showed in similarity, except high level of crude fat in rice flour and rice starch harvested in 2002. In SEM, the surface of aged rice flour had slightly layered shape due to possible abrasion during storage, and that of aged starch showed more smooth and less rigid polygonal shape. X-ray diffraction patterns of flours and starches were all A type, and crystallinity of rice starch harvested in 2000 had the smallest. From tristimulus colorimetry (Hunterlab Color), total color difference ($\Delta$E) calculated from L, a, and b gave less color difference with the darkest in 2002 harvested one among flours and the lightest in 2001 one among starches. WBCs of both 2002 rice flour and starch were the lowest among samples studied. At 80$^{\circ}C$, swelling power and solubility of rice starches harvested in 2000, 2001 and 2002 were 14.35, 9.75; 14.04, 9.6; and 12.49, 8.82, respectively. The highest peak viscosities measured by RVA were shown both in 2001 rice flour and in its starch. Starch and milled rice flour harvested in 2000 had higher hydrolytic $\alpha$-amylase, compared to other flour and starch samples.

• 대한가정학회지
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• 제8권1호
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• pp.100-119
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• 1970

In finding an improved and generalized method of making Jung-pyun, a type of scientific experimental cookey has been attempted with the use of yeast in place of Korean native rice wine named "Takju" The result is shown as follows; 1. Starta prepared with yeast and rice powder was mixed again with fresh rice powder as fermenting and aging agents in Jung-pyum making. 2. Recommendable methods of starta making are shown as follows; a. Recipe Rice powder--Certain amount Yeast--1% Sugar--10% Water--65%(by volume) b. Temperature and Time of Fermentation Temperature--30$^{\circ}C$ Time--20 hrs. 3. Recommendable method of dough making are shown as follows; a. Recipe Starta--Certain amount Rice powder--Two times the starta(2-3 times) Sugar--10% Water--50%(by volume) b. Temperature and Time of Aging Temperature--35$^{\circ}C$ Time--3 hrs. (3-4 hrs) 4. Steaming Time 25-30 min.

• 농업과학연구
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• 제43권1호
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• pp.144-151
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• 2016

With an aging population in rural areas, farm owners in South Korea are also aging. In particular, this phenomenon leads to the lack of human resources in rural areas and agriculture, worsening the deterioration of the rural economy. This study aimed, firstly, to analyze the criticality of the lack of human resources and high production cost issues for farmers, before using the farm as cooperative nursery of rice seedlings. Secondly, the study analyzed farmer satisfaction after using the farm cooperative. Analysis results are as follows. The motives of the research subjects for using the co-nursery were the aging of the farming population, the expected reduction of production costs, and farmers' failure in raising seedlings. Importance-performance analysis measured the importance for the farms for cooperative raising of rice seedling at 3.49 and the performance for the farms at 3.41, with a difference of 0.07 between them. The four importance-performance matrix areas, used were as follows: concentrated efforts required (Quadrant I: concentrate here), continuous maintenance (Quadrant II: keep up the good work), gradual improvement (Quadrant III: low priority), and avoiding excessive efforts (Quadrant IV: possible overkill). Based on the results, it was concluded that improvements and efforts would be necessary for each of these areas. And, there is a need to improve services through the initiation of farmer use of this rice co-nursery.