• 한국작물학회지
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• 제52권3호
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• pp.341-347
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• 2007

Chinese milk vetch (CMV) is a winter legume that is commonly used as cover crop in Korea. Kill date of cover crop for addition into soil affects N content in cover crop and N availability in soil. This study was conducted to evaluate the effect of CMV as green manure cover crop according to kill dates before growing corn without artificial fertilizer. Top of CMV cut three times on 13 April, 27 April, and 11 May were added into soil at a rate of 600 kg per 10a. Sugar content in CMV litter was persistently decreased from mid-April to late-May. The decrease of sugar content might be due to the transformation into starch and/or other storage or structural constituents. The decreased amount of sugars was greater than 12% and the increased amount of starch was less than 0.2%. Concentration of $NH_4^+$ in soil treated by CMV litter cut on May 11 was slightly higher than that in the treatment with early-cut (April 13) CMV, the concentration at 28 and 49 DAT (days after treatment) was higher in the treatment with late-cut CMV litter. Regardless of cut (kill) date of CMV, the phosphatase activity in the treatment of CMV litter was higher compared to the untreated control. Soil dehydrogenase activity was increased steadily by addition of CMV litter implying total microbial activities in the soil were increased. Our results demonstrate that the status of cover crop species at kill date is an important factor influencing soil enzyme activities derived from microorganisms. Therefore, the optimal kill date of cover crop should be examined to improve the efficiency of cover crop as green manure crop regarding the practical sequence in cropping system.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1986년도 춘계 학술대회지
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• pp.62-63
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• 1986

• 한국유기농업학회지
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• 제10권4호
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• pp.69-78
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• 2002

춘작 재배시 가공용 감자 품종의 품질 요인을 분석하고 저장중 glucose 및 sucrose 함량과 chip color의 변화를 알기 위해하여 99년 4월 1일부터 7월 10일까지 재배한 감자 품종을 104일 동안 저장하여 춘작 재배에 가장 좋은 품질을 나타내는 품종 및 요인을 밝혀내기 위한 조사 결과는 다음과 같다. 1. 생육 중 잎의 질소 농도는 생식 행장 초기와 괴경 성숙 단계인 개화 말기에 잎의 질소 농도가 급격히 낮아지는 경향이 있었다. 2. 생육중 잎의 K+ 농도는 종생종은 70일 만생종인 snowden은 90일부터 높게 나타나 약 20일간의 차이를 보였다. 3. Snowden 품종은 춘작재배시 110일 이상 수확 일수 확보가 어려워 춘작 재배 품종으로는 부적합한 것으로 나타났다. 4. Solid 함량과 sugar 함량은 chip color에 많은 영향을 주었으며, solid가 높을수록 sugar 함량이 낮고 저장 중품질의 변화가 적었다.

• Food Science and Biotechnology
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• 제18권6호
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• pp.1398-1403
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• 2009

Present study deals with variations of physicochemicals including $\gamma$-aminobutyric acid (GABA), $\gamma$-oryzanol, free sugar, lipoxygenase activity, fat acidity, and germination rate from Korean brown rice cultivars. With increase of storage time and temperature, GABA, $\gamma$-oryzanol, lipoxygenase activity, and fat acidity increased, whereas free sugar and germination rate was reduced. Among cultivars, 'Gopumbyeo' exhibited the highest contents in GABA and $\gamma$-oryzanol during 12 weeks storage at $25^{\circ}C$ (GABA: $28.6{\pm}5.6{\rightarrow}170.4{\pm}4.6\;mg/100\;g$, $\gamma$-oryzanol: $6.1{\pm}0.7{\rightarrow}6.7{\pm}0.4\;mg/g$) and 'Ilpumbyeo' significantly decreased in free sugar during 12 weeks storage at $10^{\circ}C$ ($1,423.7{\rightarrow}1,058.4\;mg/100\;g$). Moreover, 'Taebongbyeo' exhibited the highest quality owing to low lipoxygenase activity, low fat acidity, and high germination rate. In free sugar compositions, sucrose exhibited the highest content (>70%), followed by fructose (>7%), raffinose (>5%), glucose (>3%), and maltose (>2%) during storage. Based on our results, changes of physicochemicals in stored brown rice may be important information in processing food and functional properties.

• 한국자원식물학회지
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• 제24권6호
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• pp.688-695
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• 2011

The composition of free sugar, free amino acid, and fatty acid in tubers of the cultivars 'Superior', 'Sinnamjak', and 'Chubaek' were evaluated at the two sites with different altitude, Gangneung (20 m altitude) as lowland and Daekwallyeong (760 m altitude) as highland. The average reducing sugar content of the three potato cultivars harvested in Daekwallyeong and Gangneung was 1.1% and 2.3%, respectively, which showed two-fold difference between the two locations. Average total sugar content was also two-folds lower in potatoes harvested in Daekwallyeong (6.3%) than those harvested in Gangneung (12.2%). Average content of free amino acids of the three potato cultivars harvested in Daekwallyeong and Gangneung was 1,325 mg/100g and 1,051 mg/100g, respectively. The cultivar 'Chubaek' has the highest amino acid content among the three tested cultivars. Potatoes from Daekwallyeong have higher unsaturated fatty acid levels than those from Gangneung. During the tuber development, unsaturated fatty acids levels increased in tubers grown in Daekwallyeong, but decreased in those grown in Gangneung. These results indicate that the quality of potatoes from Daekwallyeong is from Gangneung for food processing purpose for human consumption.

• 한국환경농학회지
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• 제35권4호
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• pp.247-255
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• 2016

BACKGROUND: Acrylamide (CAS No. 79-06-1) is known to be a carcinogenic compound, and is classified as a Group 2A compound by the International Agency for Research on Cancer (IARC, 1994). Acrylamide can be generated during the browning process via the non-enzymatic Maillard reaction of carbohydrates such as reducing sugars and of amino acids such as asparagine, both of which occur at a temperature above $120^{\circ}C$. Potato tubers contain reducing sugars, and thus, this will affect the safety of processed potato products such as potato chips and French fries. In order to reduce the level of acrylamide in potato processed products, it is therefore necessary to understand factors that affect the reducing sugar content of potatoes, such as environmental factors and potato storage conditions, as well as understanding factors affecting acrylamide formation during potato processing itself. METHODS AND RESULTS: Potatoes were cultivated in eight regions of Korea; For each of these different environments, soil physico-chemical characteristics such as pH, electrical conductivity, total nitrogen, available phosphate, and exchangeable cation content were measured and correlations with potato reducing sugar content and potato chip acrylamide levels were examined. The reducing sugar content in potato during storage for three months was determined and acrylamide level in potato chip was analyzed after processing. The storage temperature levels were $4^{\circ}C$, $8^{\circ}C$, or $10^{\circ}C$, respectively. The acrylamide content of chips prepared from potatoes stored at $10^{\circ}C$ or $20^{\circ}C$ for one month was analyzed and the different frying times were 2, 3, 5, and 7 min. CONCLUSION: This study showed that monitoring and controlling the phosphate content within a potato field should be sufficient to avoid producing brown or black potato chips. For potatoes stored at low temperatures, a reconditioning period ($20^{\circ}C$ for 20 days) is required in order to reduce the levels of reducing sugars in the potato and subsequently reduce the acrylamide and improve chip coloration and appearance.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 춘계 학술대회지
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• pp.134-135
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• 2000

• 한국작물학회:학술대회논문집
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• 한국작물학회 1999년도 춘계 학술대회지
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• pp.47-48
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• 1999

• 한국작물학회:학술대회논문집
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• 한국작물학회 1999년도 춘계 학술대회지
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• pp.49-50
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• 1999

• 한국작물학회:학술대회논문집
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• 한국작물학회 1999년도 춘계 학술대회지
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• pp.51-52
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• 1999