• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.89-94
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• 1985

Seventy nine swollen commercially canned grapes and peaches were collected from wholesale and retail outlets in Seoul area for the investigation of the causes of their swell. Hydrogen generation and microbial spoilage were the only two common causes of can swelling. Nevertheless, the spoilage profile of the two products was different. Seventeen out of twenty one canned peaches were spoiled by microorganisms, while the rest of five were swollen due to hydrogen generation. In contrast, fifty one out of fifty eight canned grapes were swollen due to hydrogen generation, while the rest of seven were spoiled by microorganisms. Seventeen yeast and five bacterial strains were isolated and only the yeasts were identified to their genera and species. Saccharomyces cerevisiae was the most frequently isolated spoilage yeast, closely followed by Torulopsis stellata. Candida parapsilosis, Pichia kluyveri, Pichia membranaefaciens, Torulopsis globosa and Torulopsis lactis-condensi were also isolated but with lower frequencies.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.5
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• pp.445-449
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• 2016

In this study, Red pearl (4x) and MBA (2x) were crossed Gangwon-do Agricultural Research and Extension Services in 2000 to compare the brewing characteristics of Cheonghyang, a seedless kind of grape registered in 2009, by maturity. Fruit characteristics of Cheonghyang were examined after the first racking and 300 days after fermentation during aging in manufacturing wine based on maturity categories of being immature, mature, and overmature after harvest between August 25 and 27, 2014. The soluble solid matter content did not differ between the first racking following manufacturing wine and during ripening, and the alcohol content following the first racking was 12.9% for immature ones, 13.0% for mature ones, and 12.7% for overmature ones., The alcohol content decreased by appropriately 1.3% to 1.8% during ripening. The total acidity content was 0.9% for immature ones, 0.8% for mature ones, and 0.5% for overmature ones following the first racking and showed insignificant variations during ripening of 0.8%, 0.7%, and 0.5%, respectively, with wine made from mature ones showing proper acidity. The volatile acid content following the first racking during ripening, showing insignificant variation by maturity; however, it decreased after ripening. The sensory evaluation detected differences in acidity of wine between mature and overmature grapes. There was no difference in sour taste between immature and mature grapes; however, overmature ones had low levels of sour taste. Our results showed that mature wine had the best overall preference.

• Food Science and Preservation
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• v.5 no.4
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• pp.315-319
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• 1998

In order to study the effect of packing materials on the quality of fares during storage period, grapes (Campbell Early) were packed with different materials such as expendable folystyrene (EPS) box, paper board box, biopaper board box, paper board box + small box, EPS box + (EPS dish + Bio-PE film sealing), md EPS box + (EPS dish + wrap sealing). The fruit weight loss was increased with the storage period by all the treatments. Weight loss was 6.38% lower in the EPS box+ (EPS dish + Bio film sealing) during 15 days of storage and 5.53% lower in EPS box + (EPS dish + wrap sealing) than that in the EPS box. The abnormal fruits were more increased in the sealing packing than in the non-sealing packing since water transpiration was prevented in the sealing treatment. Wilting fruits were also fewer in the sealing packing than that in the non-sealing treatment. The taste and appearance quality were worsened with increasing the storage days, whereas the appearance quality of the grapes in the bio paper board box was better. Hardness was scarecely changed in the EP5 box+ (EPS dish + Bio-PE film sealing) treatment than those by the other treatments. The soluble solid and acidity showed very little change but soluble solid content was more decreased in the sealing packing than that by the non-sealing treatment.

• Korean Journal of Plant Resources
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• v.23 no.3
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• pp.228-232
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• 2010

The present study was carried out to elucidate the effect of girdling on the quality and harvest date of the 'Shigyoku' grapes. Among girdled vines, the interval from full bloom to harvest date was 77 days; this was as much as seven days shorter in vines receiving a 20% girdling treatment. With regards to fruit characteristics, significant differences were observed in cluster length, berry number, and berry weight in vines that received girdling treatments. There were also significant differences in cluster weight; 468.2 g, 491.6 g and 504.9 g in the control group, 10% girdling group, and 20% girdling group, respectively. Thus, the use of girdling treatments is an effective approach to increasing cluster weight by 5% in the 10% girdling treatment and 8% in the 20% girdling treatment. The 10% girdling treatment showed significant difference in terms of titrable acidity; in fact, the overall titrable acidity was relatively high among all the girdling treatments. The concentration of anthocyanin increased in 20% girdling treatment, but there were no significant differences in anthocyanin concentration among girdling treatments. Berry color developed rapidly in vines that received girdling treatment.

• Korean Journal of Agricultural Science
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• v.29 no.1
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• pp.8-14
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• 2002

Spray of maleic hydrazide (MH) was confirmed to be highly effective on the inhibition of lateral shoot growth regardless of grape cultivars and application concentration examined in this experiment. The optimal spray times were 30 days aft er full bloom in 'Kyoho' and 35 days in 'Campbell Early'. However, the optimum season of application should be adjusted depending on the vine vigor. The apical buds of lateral shoot was significantly affected at the concentration of $3,900mg{\cdot}L^{-1}$ resulting in the death and/or abscission. Thus the optimal concentration of MH seemed to be $1,950mg{\cdot}L^{-1}$. The inhibition effect by MH application was derive d from the decrease of node number and length. No adverse effect on fruit quality was found by MH application. In contrast, there was a tendency of anthocyanin in crease in 'Campbell Early' grapes. Results indicated that MH could be an effective agent to reduce the labor charge through the inhibition of later shoot growth.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.235-241
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• 2017

The purpose of this study was to investigate the enhanced physiological activities of two Pichia strains, yeasts isolated from grapes pericarp. Based on phylogenetic analysis using 18S rRNA sequencing, two isolates were identified as Pichia manshurica GU-3 and Pichia terricola GU-4, respectively. The scanning electron microscopic analysis showed that the two isolates grown on YPD medium were of typical elliptical shape with buds and bud scars on cell surface. Physiological activities of the single and mixed Pichia cultures were monitored and compared. In mixed cultures after 72 h of incubation, the maximum activities of tyrosinase inhibition, ACE inhibition, and antioxidant were 81.7%, 45.9%, and 42.7%, respectively. Superoxide dismutase-like activity was approximately 30% in the mixed cultures. These studies demonstrate that Pichia species cultured in the form of mixture can enhance the physiological activities and has potential for the development of new bioactive products.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.782-788
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• 2010

Detail management standard on soil conditions in 'Kyoho' grapes were not yet made. Therefore, this study was carried out to investigate the optimum soil environmental conditions on production of high fruit quality in 'Kyoho' grapes. We established using correlation between fruit quality and soil condition. These results were used to develop soil management guideline with promoting efficiency and minuteness in grape vineyard. Soil conditions were analyzed at total 80 vineyards in major grape producing areas such as Ansung, and Cheonan (40 orchards an area). The soil environmental factors affected fruit weight were soil pH of 36.6%, cultivation layer depth of 23.3%, and cation of 17.8%. The soil condition factors affected sugar content were soil hardness of 24.4%, cation of 24.1% and organic matter content of 22.1%. Cultivation layer depth, soil texture, and phosphate content were low as relative contribution. Coloring was involved with organic matter content, CEC (cation exchange capacity), and saturated hydraulic conductivity. while soil pH, cultivation layer depth, and phosphate content showed low contribution. Finally, relative contribution on fruit quality related with sugar content, fruit weight, and coloring were soil hardness of 28.0%, organic matter content of 25.0%, soil pH of 12.9%.

• Journal of Practical Agriculture & Fisheries Research
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• v.7 no.1
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• pp.81-89
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• 2005

The experiment was conducted to evaluate the effect of fruit skin spray of the lime fertilizer in 'Campbell Early' grapes. The T-N, P, K, Ca and Mg of fruit skin and cluster weight, berry weight, cluster length showed no difference between control and lime fertilizer. But soluble solids in fruit was reduced by fruit skin spray of liquid calcium fertilizer extracted from oyster shell after bagging(LCaB). The anthocyanin content of fruit skin was decreased by air-slaked lime(HCa) and LCaB treatment. Also, occurrence of fruit skin bloom was significantly reduced by HCa and oyster shell powder(OS-CaP) treatment. The berry firmness was significantly increased through liquid calcium fertilizer extracted from oyster shell(LCa) and HCa treatment. Conspicuously, berry elasticity was rather decreased by OS-CaP treatment. However, there was no difference of weight loss of fruit among treatments during room temperature storage.

• Food Science and Preservation
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• v.30 no.2
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• pp.321-333
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• 2023

The study investigated the pH, acidity, soluble solids, total sugar, polyphenol, flavonoid, anthocyanin content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, and color of kombucha with a variety of added fruit peels during the fermentation process. Pear, grape, plum, orange, apple, and golden kiwi peels were added during fermentation. The pH showed a decrease, while an increase in acidity was observed. An increase in soluble solids, which was higher in most experimental groups than the control group, was also observed. A decrease in total sugar was observed over time. However, an increase was observed in reducing sugar. On Day 0, higher total sugar and reducing sugar were detected in the peel addition group compared with the control group. The antioxidant capacity of polyphenol, flavonoid, anthocyanins, and DPPH radicals scavenging increased with fermentation and was higher in all addition groups, except for pear, compared with the control group. Except for grapes and plums containing high levels of anthocyanins, an increase in the L-value was observed over time, and an increase in the a-value of grapes and plums was also observed (p<0.05). The possible utilization of inedible fruit peel in kombucha was shown. Applying inedible fruit peels to kombucha is proposed to increase antioxidant content and modulate color and pH.

• The Korean Journal of Mycology
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• v.51 no.3
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• pp.179-190
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• 2023

Grapevine downy mildew, caused by Plasmopara viticola, significantly damages vineyards and is one of the most devastating diseases affecting cultivated grapes worldwide. In this study, we characterized the phenotypic and molecular traits of 11 P. viticola isolates from four grape-growing regions in South Korea. Additionally, we investigated the diversity of pathogenicity among these isolates and conducted an assay to evaluate the response of grape cultivars to P. viticola infection. Lemon-shaped sporangia were identified in the collected isolates, which released zoospores into the suspension at room temperature. Within a few hours of inoculation, the zoospores developed germ tubes. We tested 11 P. viticola isolates for pathogenicity in 845 grape cultivars to screen for grape host resistance to downy mildew infection. Among the tested isolates, JN-9 showed the highest virulence. Grape cultivars displayed varying phenotypic reactions to P. viticola infection: approximately 7% were highly susceptible, 41% were susceptible, 20% were moderately susceptible, 8% were resistant, and 24% exhibited extreme resistance. Phylogenetic analysis based on four genomic regions (internal transcribed spacer 1 [ITS1], actin, beta-tubulin, and cytochrome c oxidase II) revealed a close evolutionary relationship among all the Korean isolates, forming a single monophyletic lineage. Notably, these isolates showed greater similarity to European isolates than to American isolates. This comprehensive study contributes to a deeper understanding of the identity and behavior of P. viticola, which is crucial for developing effective resistance strategies against this pathogen in grape cultivars cultivated in South Korea.