• Food Science and Preservation
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• v.7 no.3
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• pp.241-244
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• 2000

Grapes(Vitis labruscana B) were fumigated with acetic acid at 20mg/liter to reduce storage decay and packaged with polyethylene film(0.03mm), then stored for 90 days at 2$^{\circ}C$. Modified atmosphere packaging reduced slightly weight loss and soluble solids content during storage. Acetic acid fumigation decreased effectively berry shattering and achieved remarkable control of rotting for storage. Two grape cultivars, 'Campbell Early' and 'Sheridan', fumigated with acetic acid had only 0.7~2.9 berries rot compared with 8.3~27.6 berries rot of cluster for grapes that were not fumigated.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.5
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• pp.399-407
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• 2013

Organic grape was generally produced in rainshield or plastic greenhouse culture while most of fruits were produced in open field. But little attention has been given to soil properties with different culture facilities in organic grape cultivation. This study was conducted to investigate soil physico-chemical properties of organic grapes farms with different culture facilities and soil management practices. Organic fertilizer was main resource to manage soil at organic grapes farms. Organic grapes farms were applied with total amount of organic fertilizer at one time, either at basal or additional fertilization, whereas conventional grapes farms applied with split fertilization. Bulk density and penetration resistance of soil were lower at both rainshield and green manure-applied plastic greenhouse cultures than those at clean plastic greenhouse culture. Especially, in plastic greenhouse, sod culture with natural weed after green manure application was more effective than general sod culture in improving physical properties of the rhizosphere. The contents of organic matter, available phosphate and exchangeable potassium tended to increase in the soils applied with green manure, and the difference of soil chemical properties were significant between rainshield and plastic greenhouse cultures. The optimum soil management was required in plastic greenhouse because pH, available phosphate and exchangeable cations reached over optimum range. Consequently, the ground cover management is the key factor to affect the chemical properties as well as soil physical properties extensively in plastic greenhouse. It is found that sod culture with natural weed after green manure application resulted in enhancement of utilization efficiency of nitrogen, phosphoric acid and potassium in soil in comparison with general sod culture.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.762-767
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• 2010

This study was conducted to investigate the influence of formulation of fungicides on epicuticular waxes in 'Campbell Early' grapes. Non-bagged and bagged berries were treated with wettable powder, suspension concentrate and emulsifiable concentrate 15 days after full bloom (DAFB) and 48 DAFB (veraison), respectively. Fruit skin was observed by naked eye and scanning electron microscope (SEM) at harvest. Remarkable white blots were observed on the berries treated 48 DAFB in the order of wettable powder, suspension concentrate, and emulsifiable concentrate. The observation by SEM showed all formulations of fungicides damaged the ultra-structure of epicuticular waxes; also, an unknown substance was observed on treatment with wettable powder and suspension concentrate. Moreover epicuticular wax appeared to be melting on the grapes treated with emulsifiable concentrate. Also, non-bagged grapes showed serious contamination of epicuticular wax by some unknown substance, but bagged grapes had only fungicides' traces.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.2
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• pp.222-227
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• 2011

The Aspergillus sp. is well known as a fungus that causes black mold disease and secretes ochratoxin A (OTA). Our study found that infection by this fungus via inoculation onto grapes produced more severe symptom in wounded berries than in fresh berries. Furthermore, OTA contents were higher on the grape skins than in the fleshy portions of the grapes. OTA accumulated during the first 3 days after inoculation, but then gradually decreased. The OTA contents in wine made from 5 kg of grapes which included 400 g of infected grapes ranged from 0.17 to 0.37 ${\mu}g/mL$. An investigation of 25 marketed commercial wines showed the OTA contents were <1.2 ${\mu}g/mL$ which is lower than the limit of 2 ${\mu}g/mL$ established by the Korea Food & Drug Administration.

• Korean journal of applied entomology
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• v.1
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• pp.47-50
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• 1962

Ripe rot, caused by Glomerlla cingulata is the most destructive disease of grapes in korea. this experiment was to determine the most effective control teratment for ripe rot of grapes. The variety, Campbell Early, was used in the trials planted on land managed by the Pomology Section of the Horticultural Experiment Station. This experiment indicated that Tuzet and Delan-wp were most effective in the control of ripe rot of grapes either with or without bagging in 1962.

• Natural Product Sciences
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• v.10 no.5
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• pp.248-251
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• 2004

Resveratrol has been reported to possess a variety of biological and pharmaceutical activities. Regardless of its beneficial effects on health, the amount of resveratrol in grapes is very low. In order to induce the resveratrol biosynthesis, the promoter region of a genomic fragment encoding the resveratrol synthase was isolated and a molecular switch was identified which provides us with defining biotic or abiotic inducers that transcriptionally up-regulate the gene expression involved in the resveratrol biosynthesis. We could successfully increase the amount of resveratrol in grapes up to 3-fold by using these environmental factors.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.615-641
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• 2015

This study analyzes an economic efficiencies of apples, pears, and grapes farming. We evaluate an annual economic overall efficiency (OE), allocative efficiency (AE), technology efficiency (TE), pure technology efficiency (PTE), and scale efficiency (SE) using data envelopment analysis (DEA). We also measure returns to scale of farms, and the change of technical efficiency of frontier farms. Lastly we estimate the effects of some explanatory variables on allocative, pure technical, and scale efficiencies.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.739-745
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• 2011

This study was performed to investigate the enrichment of resveratrol content in harvested grapes using the modulation of cell metabolism with ultra-violet (UV) irradiation. Resveratrol, a phytoalexin, is produced by stilbene synthase (STSY) from malonyl-CoA and ${\rho}$-coumaroyl-CoA. Its biosynthesis has been reported to be induced by UV and other environmental factors. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis showed that STSY Promoter 1 in grapes was very highly expressed by treatment with UV. Grapes were harvested and treated for post-harvest induction of STSY gene expression with UV, and then their resveratrol content was analyzed. UV treatment for 5 minutes provided the best condition for the induction of STSY gene expression. When harvested Gerbong and MBA grapes were treated with a prototype UV radiator, their resveratrol content was enriched upto 5 times compared with untreated grapes. These results suggest that a post-harvest UV treatment can be applied to enrich resveratrol content in grapes and add value to them.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.739-745
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• 2015

To maintain quality of Delaware grapes during storage, grape samples were treated with 0.1% chitosan dissolved in 0.5% acetic acid, packaged with low density polyethylene film, and stored at 4 or $20^{\circ}C$ for 12 days. Chitosan treatment reduced initial populations of yeast and molds in grapes by 1.86 log CFU/g compared to that of the control. During storage, oxygen contents in packages of samples decreased, whereas carbon dioxide contents increased. In addition, regardless of storage temperature, changes in oxygen and carbon dioxide concentrations of grapes treated with chitosan were lower than those of the control. Hardness of samples decreased, and Hunter L, a, and b values were not significantly different among treatments. Regarding pH and total soluble content, grapes stored at $4^{\circ}C$ maintained pH and had greater total soluble content than those stored at $20^{\circ}C$. These results suggest that chitosan treatment and low temperature storage can be useful for maintaining microbiological safety and quality of Delaware grapes during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.190-195
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• 1993

In order to investigate the changes of some chemical components during the maturation of Vitis vinifera red grapes, brix, total sugar, organic acids, total acid, pH and free amino acids were analyzed by HPLC etc. Brix, pH and total sugar content during the maturation of red grapes were increased rapidly but total acidity was decreased between 12~14 days after the formation of sugars. Its compositions were 16.5~17.9 of brix, 14.8~16.4g/100ml of total sugar, 3.24~3.25 of pH and 0.81~0.92g/100ml of total acidity. The ratio of brix/acid was increased gradually during the maturation. Glucose and fructose were contained more than 99% of total sugar and the content of sucrose were 0.03~0.04g/100ml in three varieties (Cabernet sauvignon, Cabernet franc and Malbec). The ratio of fructose/glucose in maturated three red grapes was ranged 1.04~1.06. Organic acids during the maturation, when sugars increased, were decreased rapidly and the ratio of tartaric/malic acid showed 0.83~1.00. Free amino acids during the maturation were increased and these content were 256.8mg~290.9mg/100ml in three varieties. The content of proline was the highest content of free amino acids in three red grapes, the next ones were arginine, alanine and glutamic acid in the other with 73.2~77.2% of total free amino acids. Especially, content of arginine was higher than others in Malbec variety.